diff --git a/CMakeLists.txt b/CMakeLists.txt
index 781e98a23..a0606e348 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1424,6 +1424,7 @@ else()
 endif()
 
 
+
 ################################################################################
 # Abseil C++ - https://abseil.io/docs/cpp/
 ################################################################################
@@ -3339,7 +3340,7 @@ set_package_properties(LIBIIO PROPERTIES
     PURPOSE "Used for communication with the AD9361 chipset."
     TYPE OPTIONAL
 )
-if(ENABLE_AD9361 OR ENABLE_FMCOMMS2)
+if(ENABLE_AD9361 OR ENABLE_FMCOMMS2 OR ENABLE_PLUTOSDR)
     if(NOT LIBIIO_FOUND)
         message(STATUS "libiio not found, its installation is required.")
         message(STATUS "Please build and install the following projects:")
@@ -3360,6 +3361,9 @@ endif()
 ################################################################################
 # ION GNSS-SDR Metadata Standard https://sdr.ion.org/ (OPTIONAL)
 ################################################################################
+if(CMAKE_VERSION VERSION_LESS 3.14)
+    set(ENABLE_ION OFF)  # FetchContent_MakeAvailable is available from CMake 3.14
+endif()
 if(ENABLE_ION)
     include(FetchContent)
     set(CMAKE_POLICY_DEFAULT_CMP0063 NEW)
diff --git a/src/algorithms/signal_source/adapters/CMakeLists.txt b/src/algorithms/signal_source/adapters/CMakeLists.txt
index 6b58e1abe..5f5d4ce3b 100644
--- a/src/algorithms/signal_source/adapters/CMakeLists.txt
+++ b/src/algorithms/signal_source/adapters/CMakeLists.txt
@@ -244,7 +244,7 @@ if(ENABLE_LIMESDR AND GRLIMESDR_FOUND)
     )
 endif()
 
-if(ENABLE_AD9361 AND LIBIIO_FOUND)
+if(LIBIIO_FOUND)
     target_link_libraries(signal_source_adapters
         PRIVATE
             Iio::iio
diff --git a/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.cc b/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.cc
index 9d29e2de2..cc8f7fe32 100644
--- a/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.cc
+++ b/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.cc
@@ -1,6 +1,6 @@
 /*!
  * \file adrv9361_z7035_signal_source_fpga.cc
- * \brief signal source for the Analog Devices ADRV9361-Z7035 evaluation board
+ * \brief Signal source for the Analog Devices ADRV9361-Z7035 evaluation board
  * directly connected to the FPGA accelerators.
  * This source implements only the AD9361 control. It is NOT compatible with
  * conventional SDR acquisition and tracking blocks.
@@ -257,7 +257,6 @@ Adrv9361z7035SignalSourceFPGA::Adrv9361z7035SignalSourceFPGA(const Configuration
     buffer_monitor_fpga = std::make_shared<Fpga_buffer_monitor>(num_freq_bands, dump_, dump_filename);
     thread_buffer_monitor = std::thread([&] { run_buffer_monitor_process(); });
 
-
     // dynamic bits selection
     if (enable_dynamic_bit_selection_)
         {
@@ -278,15 +277,23 @@ Adrv9361z7035SignalSourceFPGA::Adrv9361z7035SignalSourceFPGA(const Configuration
 
 Adrv9361z7035SignalSourceFPGA::~Adrv9361z7035SignalSourceFPGA()
 {
-    /* cleanup and exit */
-
+    // cleanup and exit
     if (rf_shutdown_)
         {
             std::cout << "* AD9361 Disabling RX streaming channels\n";
-            if (!disable_ad9361_rx_local())
+            try
                 {
-                    LOG(WARNING) << "Problem shutting down the AD9361 RX channels";
+                    if (!disable_ad9361_rx_local())
+                        {
+                            LOG(WARNING) << "Problem shutting down the AD9361 RX channels";
+                        }
                 }
+            catch (const std::exception &e)
+                {
+                    LOG(WARNING) << "Problem shutting down the AD9361 RX channels: " << e.what();
+                    std::cerr << "Problem shutting down the AD9361 RX channels: " << e.what() << '\n';
+                }
+
             if (enable_dds_lo_)
                 {
                     try
@@ -301,24 +308,27 @@ Adrv9361z7035SignalSourceFPGA::~Adrv9361z7035SignalSourceFPGA()
         }
 
     // disable buffer overflow checking and buffer monitoring
-    std::unique_lock<std::mutex> lock_buffer_monitor(buffer_monitor_mutex);
-    enable_ovf_check_buffer_monitor_active_ = false;
-    lock_buffer_monitor.unlock();
+    {
+        std::lock_guard<std::mutex> lock_buffer_monitor(buffer_monitor_mutex);
+        enable_ovf_check_buffer_monitor_active_ = false;
+    }
 
     if (thread_buffer_monitor.joinable())
         {
             thread_buffer_monitor.join();
         }
-
-    std::unique_lock<std::mutex> lock_dyn_bit_sel(dynamic_bit_selection_mutex);
-    bool bit_selection_enabled = enable_dynamic_bit_selection_;
-    lock_dyn_bit_sel.unlock();
+    bool bit_selection_enabled = false;
+    {
+        std::lock_guard<std::mutex> lock_dyn_bit_sel(dynamic_bit_selection_mutex);
+        bit_selection_enabled = enable_dynamic_bit_selection_;
+    }
 
     if (bit_selection_enabled == true)
         {
-            std::unique_lock<std::mutex> lock(dynamic_bit_selection_mutex);
-            enable_dynamic_bit_selection_ = false;
-            lock.unlock();
+            {
+                std::lock_guard<std::mutex> lock(dynamic_bit_selection_mutex);
+                enable_dynamic_bit_selection_ = false;
+            }
 
             if (thread_dynamic_bit_selection.joinable())
                 {
@@ -337,12 +347,11 @@ void Adrv9361z7035SignalSourceFPGA::run_dynamic_bit_selection_process()
             // setting the bit selection to the top bits
             dynamic_bit_selection_fpga->bit_selection();
             std::this_thread::sleep_for(std::chrono::milliseconds(Gain_control_period_ms));
-            std::unique_lock<std::mutex> lock(dynamic_bit_selection_mutex);
+            std::lock_guard<std::mutex> lock(dynamic_bit_selection_mutex);
             if (enable_dynamic_bit_selection_ == false)
                 {
                     dynamic_bit_selection_active = false;
                 }
-            lock.unlock();
         }
 }
 
@@ -357,12 +366,11 @@ void Adrv9361z7035SignalSourceFPGA::run_buffer_monitor_process()
         {
             buffer_monitor_fpga->check_buffer_overflow_and_monitor_buffer_status();
             std::this_thread::sleep_for(std::chrono::milliseconds(buffer_monitor_period_ms));
-            std::unique_lock<std::mutex> lock(buffer_monitor_mutex);
+            std::lock_guard<std::mutex> lock(buffer_monitor_mutex);
             if (enable_ovf_check_buffer_monitor_active_ == false)
                 {
                     enable_ovf_check_buffer_monitor_active = false;
                 }
-            lock.unlock();
         }
 }
 
diff --git a/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.h b/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.h
index 5e7e8b7e4..beffb3c70 100644
--- a/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.h
+++ b/src/algorithms/signal_source/adapters/adrv9361_z7035_signal_source_fpga.h
@@ -1,6 +1,6 @@
 /*!
  * \file adrv9361_z7035_signal_source_fpga.h
- * \brief signal source for the Analog Devices ADRV9361-Z7035 evaluation board
+ * \brief Signal source for the Analog Devices ADRV9361-Z7035 evaluation board
  * directly connected to the FPGA accelerators.
  * This source implements only the AD9361 control. It is NOT compatible with
  * conventional SDR acquisition and tracking blocks.
@@ -78,13 +78,14 @@ private:
     const uint32_t buffer_monitor_period_ms = 1000;
     // buffer overflow and buffer monitoring initial delay
     const uint32_t buffer_monitoring_initial_delay_ms = 2000;
-    // sample block size when running in post-processing mode
-    const int sample_block_size = 16384;
     const int32_t switch_to_real_time_mode = 2;
 
     void run_dynamic_bit_selection_process();
     void run_buffer_monitor_process();
 
+    mutable std::mutex dynamic_bit_selection_mutex;
+    mutable std::mutex buffer_monitor_mutex;
+
     std::thread thread_dynamic_bit_selection;
     std::thread thread_buffer_monitor;
 
@@ -92,9 +93,6 @@ private:
     std::shared_ptr<Fpga_dynamic_bit_selection> dynamic_bit_selection_fpga;
     std::shared_ptr<Fpga_buffer_monitor> buffer_monitor_fpga;
 
-    std::mutex dynamic_bit_selection_mutex;
-    std::mutex buffer_monitor_mutex;
-
     std::string gain_mode_rx1_;
     std::string gain_mode_rx2_;
     std::string rf_port_select_;
diff --git a/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.cc b/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.cc
index d8c5a65c0..be2108aa4 100644
--- a/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.cc
+++ b/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.cc
@@ -1,6 +1,6 @@
 /*!
  * \file fmcomms5_signal_source_fpga.cc
- * \brief signal source for the Analog Devices FMCOMMS5 directly connected
+ * \brief Signal source for the Analog Devices FMCOMMS5 directly connected
  * to the FPGA accelerators.
  * This source implements only the AD9361 control. It is NOT compatible with
  * conventional SDR acquisition and tracking blocks.
@@ -217,7 +217,6 @@ Fmcomms5SignalSourceFPGA::Fmcomms5SignalSourceFPGA(const ConfigurationInterface
     buffer_monitor_fpga = std::make_shared<Fpga_buffer_monitor>(num_freq_bands, dump_, dump_filename);
     thread_buffer_monitor = std::thread([&] { run_buffer_monitor_process(); });
 
-
     // dynamic bits selection
     if (enable_dynamic_bit_selection_)
         {
@@ -238,36 +237,45 @@ Fmcomms5SignalSourceFPGA::Fmcomms5SignalSourceFPGA(const ConfigurationInterface
 
 Fmcomms5SignalSourceFPGA::~Fmcomms5SignalSourceFPGA()
 {
-    /* cleanup and exit */
-
+    // cleanup and exit
     if (rf_shutdown_)
         {
             std::cout << "* Disabling RX streaming channels\n";
-            if (!disable_ad9361_rx_local())
+            try
                 {
-                    LOG(WARNING) << "Problem shutting down the AD9361 RX channels";
+                    if (!disable_ad9361_rx_local())
+                        {
+                            LOG(WARNING) << "Problem shutting down the AD9361 RX channels";
+                        }
+                }
+            catch (const std::exception &e)
+                {
+                    std::cerr << "Problem shutting down the AD9361 RX channels: " << e.what() << '\n';
                 }
         }
 
     // disable buffer overflow checking and buffer monitoring
-    std::unique_lock<std::mutex> lock_buffer_monitor(buffer_monitor_mutex);
-    enable_ovf_check_buffer_monitor_active_ = false;
-    lock_buffer_monitor.unlock();
+    {
+        std::lock_guard<std::mutex> lock_buffer_monitor(buffer_monitor_mutex);
+        enable_ovf_check_buffer_monitor_active_ = false;
+    }
 
     if (thread_buffer_monitor.joinable())
         {
             thread_buffer_monitor.join();
         }
-
-    std::unique_lock<std::mutex> lock_dyn_bit_sel(dynamic_bit_selection_mutex);
-    bool bit_selection_enabled = enable_dynamic_bit_selection_;
-    lock_dyn_bit_sel.unlock();
+    bool bit_selection_enabled = false;
+    {
+        std::lock_guard<std::mutex> lock_dyn_bit_sel(dynamic_bit_selection_mutex);
+        bit_selection_enabled = enable_dynamic_bit_selection_;
+    }
 
     if (bit_selection_enabled == true)
         {
-            std::unique_lock<std::mutex> lock(dynamic_bit_selection_mutex);
-            enable_dynamic_bit_selection_ = false;
-            lock.unlock();
+            {
+                std::lock_guard<std::mutex> lock(dynamic_bit_selection_mutex);
+                enable_dynamic_bit_selection_ = false;
+            }
 
             if (thread_dynamic_bit_selection.joinable())
                 {
@@ -286,12 +294,11 @@ void Fmcomms5SignalSourceFPGA::run_dynamic_bit_selection_process()
             // setting the bit selection to the top bits
             dynamic_bit_selection_fpga->bit_selection();
             std::this_thread::sleep_for(std::chrono::milliseconds(Gain_control_period_ms));
-            std::unique_lock<std::mutex> lock(dynamic_bit_selection_mutex);
+            std::lock_guard<std::mutex> lock(dynamic_bit_selection_mutex);
             if (enable_dynamic_bit_selection_ == false)
                 {
                     dynamic_bit_selection_active = false;
                 }
-            lock.unlock();
         }
 }
 
@@ -306,12 +313,11 @@ void Fmcomms5SignalSourceFPGA::run_buffer_monitor_process()
         {
             buffer_monitor_fpga->check_buffer_overflow_and_monitor_buffer_status();
             std::this_thread::sleep_for(std::chrono::milliseconds(buffer_monitor_period_ms));
-            std::unique_lock<std::mutex> lock(buffer_monitor_mutex);
+            std::lock_guard<std::mutex> lock(buffer_monitor_mutex);
             if (enable_ovf_check_buffer_monitor_active_ == false)
                 {
                     enable_ovf_check_buffer_monitor_active = false;
                 }
-            lock.unlock();
         }
 }
 
diff --git a/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.h b/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.h
index 1bdcf4e6f..1c5c37c73 100644
--- a/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.h
+++ b/src/algorithms/signal_source/adapters/fmcomms5_signal_source_fpga.h
@@ -1,6 +1,6 @@
 /*!
  * \file fmcomms5_signal_source_fpga.h
- * \brief signal source for the Analog Devices FMCOMMS5 directly connected
+ * \brief Signal source for the Analog Devices FMCOMMS5 directly connected
  * to the FPGA accelerators.
  * This source implements only the AD9361 control. It is NOT compatible with
  * conventional SDR acquisition and tracking blocks.
@@ -67,7 +67,6 @@ private:
     const std::string default_dump_filename = std::string("FPGA_buffer_monitor_dump.dat");
     const std::string default_rf_port_select = std::string("A_BALANCED");
     const std::string default_gain_mode = std::string("slow_attack");
-    const double default_tx_attenuation_db = -10.0;
     const double default_manual_gain_rx1 = 64.0;
     const double default_manual_gain_rx2 = 64.0;
     const uint64_t default_bandwidth = 12500000;
@@ -78,13 +77,14 @@ private:
     const uint32_t buffer_monitor_period_ms = 1000;
     // buffer overflow and buffer monitoring initial delay
     const uint32_t buffer_monitoring_initial_delay_ms = 2000;
-    // sample block size when running in post-processing mode
-    const int sample_block_size = 16384;
     const int32_t switch_to_real_time_mode = 2;
 
     void run_dynamic_bit_selection_process();
     void run_buffer_monitor_process();
 
+    mutable std::mutex dynamic_bit_selection_mutex;
+    mutable std::mutex buffer_monitor_mutex;
+
     std::thread thread_dynamic_bit_selection;
     std::thread thread_buffer_monitor;
 
@@ -92,9 +92,6 @@ private:
     std::shared_ptr<Fpga_dynamic_bit_selection> dynamic_bit_selection_fpga;
     std::shared_ptr<Fpga_buffer_monitor> buffer_monitor_fpga;
 
-    std::mutex dynamic_bit_selection_mutex;
-    std::mutex buffer_monitor_mutex;
-
     std::string gain_mode_rx1_;
     std::string gain_mode_rx2_;
     std::string rf_port_select_;
diff --git a/src/algorithms/signal_source/adapters/ion_gsms_signal_source.cc b/src/algorithms/signal_source/adapters/ion_gsms_signal_source.cc
index b67ec8a3a..2def04c75 100644
--- a/src/algorithms/signal_source/adapters/ion_gsms_signal_source.cc
+++ b/src/algorithms/signal_source/adapters/ion_gsms_signal_source.cc
@@ -19,9 +19,8 @@
 #include "gnss_sdr_string_literals.h"
 #include "gnss_sdr_valve.h"
 #include <gnuradio/blocks/copy.h>
-#include <string>
+#include <cstdlib>
 #include <unordered_set>
-#include <vector>
 
 #if USE_GLOG_AND_GFLAGS
 #include <glog/logging.h>
@@ -59,7 +58,6 @@ IONGSMSSignalSource::IONGSMSSignalSource(const ConfigurationInterface* configura
     : SignalSourceBase(configuration, role, "ION_GSMS_Signal_Source"s),
       stream_ids_(parse_comma_list(configuration->property(role + ".streams"s, ""s))),
       metadata_filepath_(configuration->property(role + ".metadata_filename"s, "../data/example_capture_metadata.sdrx"s)),
-      timestamp_clock_offset_ms_(configuration->property(role + ".timestamp_clock_offset_ms"s, 0.0)),
       in_streams_(in_streams),
       out_streams_(out_streams)
 {
@@ -88,6 +86,7 @@ IONGSMSSignalSource::IONGSMSSignalSource(const ConfigurationInterface* configura
         }
 }
 
+
 void IONGSMSSignalSource::load_metadata()
 {
     try
@@ -117,6 +116,7 @@ void IONGSMSSignalSource::load_metadata()
         }
 }
 
+
 std::vector<IONGSMSFileSource::sptr> IONGSMSSignalSource::make_stream_sources(const std::vector<std::string>& stream_ids) const
 {
     std::vector<IONGSMSFileSource::sptr> sources{};
@@ -180,6 +180,7 @@ std::vector<IONGSMSFileSource::sptr> IONGSMSSignalSource::make_stream_sources(co
     return sources;
 }
 
+
 void IONGSMSSignalSource::connect(gr::top_block_sptr top_block)
 {
     std::size_t cumulative_index = 0;
diff --git a/src/algorithms/signal_source/adapters/ion_gsms_signal_source.h b/src/algorithms/signal_source/adapters/ion_gsms_signal_source.h
index 31d0f7815..fd0a5140c 100644
--- a/src/algorithms/signal_source/adapters/ion_gsms_signal_source.h
+++ b/src/algorithms/signal_source/adapters/ion_gsms_signal_source.h
@@ -15,8 +15,8 @@
  */
 
 
-#ifndef GNSS_SDR_ION_METADATA_STANDARD_SIGNAL_SOURCE_H
-#define GNSS_SDR_ION_METADATA_STANDARD_SIGNAL_SOURCE_H
+#ifndef GNSS_SDR_ION_GSMS_SIGNAL_SOURCE_H
+#define GNSS_SDR_ION_GSMS_SIGNAL_SOURCE_H
 
 #include "configuration_interface.h"
 #include "file_source_base.h"
@@ -73,7 +73,6 @@ private:
 
     gnss_shared_ptr<Gnss_Sdr_Timestamp> timestamp_block_;
     std::string timestamp_file_;
-    double timestamp_clock_offset_ms_;
 
     uint32_t in_streams_;
     uint32_t out_streams_;
@@ -82,4 +81,4 @@ private:
 
 /** \} */
 /** \} */
-#endif  // GNSS_SDR_ION_METADATA_STANDARD_SIGNAL_SOURCE_H
+#endif  // GNSS_SDR_ION_GSMS_SIGNAL_SOURCE_H
diff --git a/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.cc b/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.cc
index 788b50e77..80b310034 100644
--- a/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.cc
+++ b/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.cc
@@ -140,13 +140,11 @@ MAX2771EVKITSignalSourceFPGA::MAX2771EVKITSignalSourceFPGA(const ConfigurationIn
         }
 }
 
+
 std::vector<uint32_t> MAX2771EVKITSignalSourceFPGA::setup_regs(void)
 {
-    std::vector<uint32_t> register_values = std::vector<uint32_t>(MAX2771_NUM_REGS);
-
-
+    auto register_values = std::vector<uint32_t>(MAX2771_NUM_REGS);
     uint32_t LNA_mode = (LNA_active_) ? 0x0 : 0x2;
-
     uint32_t Filter_Bandwidth;
 
     switch (bandwidth_)
@@ -376,10 +374,10 @@ bool MAX2771EVKITSignalSourceFPGA::configure(std::vector<uint32_t> register_valu
     return 0;
 }
 
+
 MAX2771EVKITSignalSourceFPGA::~MAX2771EVKITSignalSourceFPGA()
 {
-    /* cleanup and exit */
-
+    // cleanup and exit
     if (rf_shutdown_)
         {
             chipen_ = false;
@@ -392,7 +390,6 @@ MAX2771EVKITSignalSourceFPGA::~MAX2771EVKITSignalSourceFPGA()
                     return;
                 }
 
-
             if (configure(register_values))
                 {
                     std::cerr << "Error disabling the MAX2771 device " << '\n';
@@ -405,9 +402,10 @@ MAX2771EVKITSignalSourceFPGA::~MAX2771EVKITSignalSourceFPGA()
         }
 
     // disable buffer overflow checking and buffer monitoring
-    std::unique_lock<std::mutex> lock_buffer_monitor(buffer_monitor_mutex);
-    enable_ovf_check_buffer_monitor_active_ = false;
-    lock_buffer_monitor.unlock();
+    {
+        std::lock_guard<std::mutex> lock_buffer_monitor(buffer_monitor_mutex);
+        enable_ovf_check_buffer_monitor_active_ = false;
+    }
 
     if (thread_buffer_monitor.joinable())
         {
@@ -426,12 +424,11 @@ void MAX2771EVKITSignalSourceFPGA::run_buffer_monitor_process()
         {
             buffer_monitor_fpga->check_buffer_overflow_and_monitor_buffer_status();
             std::this_thread::sleep_for(std::chrono::milliseconds(buffer_monitor_period_ms));
-            std::unique_lock<std::mutex> lock(buffer_monitor_mutex);
+            std::lock_guard<std::mutex> lock(buffer_monitor_mutex);
             if (enable_ovf_check_buffer_monitor_active_ == false)
                 {
                     enable_ovf_check_buffer_monitor_active = false;
                 }
-            lock.unlock();
         }
 }
 
diff --git a/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.h b/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.h
index 3008aa384..5ba036ca3 100644
--- a/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.h
+++ b/src/algorithms/signal_source/adapters/max2771_evkit_signal_source_fpga.h
@@ -53,7 +53,6 @@ public:
 
     std::vector<uint32_t> setup_regs(void);
 
-
     inline size_t item_size() override
     {
         return item_size_;
@@ -130,14 +129,13 @@ private:
     bool configure(std::vector<uint32_t> register_values);
     void run_buffer_monitor_process();
 
+    mutable std::mutex buffer_monitor_mutex;
 
     std::thread thread_buffer_monitor;
 
     std::shared_ptr<Fpga_buffer_monitor> buffer_monitor_fpga;
     std::shared_ptr<Fpga_spidev> spidev_fpga;
 
-    std::mutex buffer_monitor_mutex;
-
     uint64_t freq_;  // frequency of local oscillator
     uint64_t sample_rate_;
 
diff --git a/src/algorithms/signal_source/gnuradio_blocks/ad936x_iio_source.cc b/src/algorithms/signal_source/gnuradio_blocks/ad936x_iio_source.cc
index 0cf885fe2..375edf7da 100644
--- a/src/algorithms/signal_source/gnuradio_blocks/ad936x_iio_source.cc
+++ b/src/algorithms/signal_source/gnuradio_blocks/ad936x_iio_source.cc
@@ -87,7 +87,7 @@ ad936x_iio_source_sptr ad936x_iio_make_source_sptr(
 
 void ad936x_iio_source::ad9361_channel_demux_and_record(ad936x_iio_samples *samples_in, int nchannels, std::vector<std::fstream> *files_out)
 {
-    int32_t current_byte = 0;
+    uint32_t current_byte = 0;
     int16_t ch = 0;
     // std::cout << "nbytes: " << samples_in->n_bytes << " nsamples: " << samples_in->n_samples << " nch: " << nchannels << "\n";
     while (current_byte < samples_in->n_bytes)
diff --git a/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.cc b/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.cc
index 034f43379..60a08ba6c 100644
--- a/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.cc
+++ b/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.cc
@@ -18,6 +18,8 @@
 #include "gnuradio/block.h"
 #include <algorithm>
 #include <cmath>
+#include <cstdlib>
+#include <iostream>
 
 #if USE_GLOG_AND_GFLAGS
 #include <glog/logging.h>
@@ -25,8 +27,6 @@
 #include <absl/log/log.h>
 #endif
 
-using namespace std::string_literals;
-
 IONGSMSFileSource::IONGSMSFileSource(
     const fs::path& metadata_filepath,
     const GnssMetadata::File& file,
@@ -46,7 +46,10 @@ IONGSMSFileSource::IONGSMSFileSource(
 
     if (!file_stream_.is_open())
         {
-            LOG(ERROR) << "ion_gsms_file_source: Unable to open the samples file: " << (data_filepath).c_str();
+            LOG(WARNING) << "ION_GSMS_Signal_Source - Unable to open the samples file: " << (data_filepath).c_str();
+            std::cerr << "ION_GSMS_Signal_Source - Unable to open the samples file: " << (data_filepath).c_str() << std::endl;
+            std::cout << "GNSS-SDR program ended.\n";
+            exit(1);
         }
 
     // Skip offset and block header
@@ -96,11 +99,13 @@ std::size_t IONGSMSFileSource::output_stream_item_size(std::size_t stream_index)
     return output_stream_item_sizes_[stream_index];
 }
 
+
 std::size_t IONGSMSFileSource::output_stream_total_sample_count(std::size_t stream_index) const
 {
     return output_stream_total_sample_counts_[stream_index];
 }
 
+
 gr::io_signature::sptr IONGSMSFileSource::make_output_signature(const GnssMetadata::Block& block, const std::vector<std::string>& stream_ids)
 {
     int nstreams = 0;
@@ -142,6 +147,7 @@ gr::io_signature::sptr IONGSMSFileSource::make_output_signature(const GnssMetada
         item_sizes);
 }
 
+
 int IONGSMSFileSource::work(
     int noutput_items,
     gr_vector_const_void_star& input_items __attribute__((unused)),
diff --git a/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.h b/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.h
index a787344bf..4a6baa7e9 100644
--- a/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.h
+++ b/src/algorithms/signal_source/gnuradio_blocks/ion_gsms.h
@@ -14,8 +14,8 @@
  * -----------------------------------------------------------------------------
  */
 
-#ifndef GNSS_SDR_ION_GNSS_SDR_METADATA_STANDARD_H
-#define GNSS_SDR_ION_GNSS_SDR_METADATA_STANDARD_H
+#ifndef GNSS_SDR_ION_GSMS_H
+#define GNSS_SDR_ION_GSMS_H
 
 #include "gnss_block_interface.h"
 #include "gnss_sdr_filesystem.h"
@@ -23,7 +23,6 @@
 #include <gnuradio/block.h>
 #include <gnuradio/sync_block.h>
 #include <cstddef>
-#include <cstdio>
 #include <fstream>
 #include <memory>
 #include <string>
@@ -31,7 +30,7 @@
 
 /** \addtogroup Signal_Source
  * \{ */
-/** \addtogroup Signal_Source_libs
+/** \addtogroup Signal_Source_gnuradio_blocks
  * \{ */
 
 class IONGSMSFileSource : public gr::sync_block
@@ -72,4 +71,4 @@ private:
 
 /** \} */
 /** \} */
-#endif  // GNSS_SDR_ION_GNSS_SDR_METADATA_STANDARD_H
+#endif  // GNSS_SDR_ION_GSMS_H
diff --git a/src/algorithms/signal_source/libs/CMakeLists.txt b/src/algorithms/signal_source/libs/CMakeLists.txt
index 4ad4caf93..bdbd3aace 100644
--- a/src/algorithms/signal_source/libs/CMakeLists.txt
+++ b/src/algorithms/signal_source/libs/CMakeLists.txt
@@ -15,7 +15,7 @@ endif()
 
 if(ENABLE_MAX2771)
     set(OPT_SIGNAL_SOURCE_LIB_SOURCES ${OPT_SIGNAL_SOURCE_LIB_SOURCES} fpga_spidev.cc)
-    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_SOURCES} fpga_spidev.h)
+    set(OPT_SIGNAL_SOURCE_LIB_HEADERS ${OPT_SIGNAL_SOURCE_LIB_HEADERS} fpga_spidev.h)
 endif()
 
 if(ENABLE_FPGA)
diff --git a/src/algorithms/signal_source/libs/ad936x_iio_custom.cc b/src/algorithms/signal_source/libs/ad936x_iio_custom.cc
index 72461bafd..ad983aa6b 100644
--- a/src/algorithms/signal_source/libs/ad936x_iio_custom.cc
+++ b/src/algorithms/signal_source/libs/ad936x_iio_custom.cc
@@ -1,6 +1,7 @@
 /*!
  * \file ad936x_iio_custom.cc
- * \brief A direct IIO custom front-end driver for the AD936x AD front-end family with special FPGA custom functionalities.
+ * \brief A direct IIO custom front-end driver for the AD936x AD front-end
+ * family with special FPGA custom functionalities.
  * \author Javier Arribas, jarribas(at)cttc.es
  * -----------------------------------------------------------------------------
  *
diff --git a/src/algorithms/signal_source/libs/ad936x_iio_custom.h b/src/algorithms/signal_source/libs/ad936x_iio_custom.h
index 83a61282a..ab58f36cc 100644
--- a/src/algorithms/signal_source/libs/ad936x_iio_custom.h
+++ b/src/algorithms/signal_source/libs/ad936x_iio_custom.h
@@ -1,6 +1,7 @@
 /*!
  * \file ad936x_iio_custom.h
- * \brief A direct IIO custom front-end driver for the AD936x AD front-end family with special FPGA custom functionalities.
+ * \brief A direct IIO custom front-end driver for the AD936x AD front-end
+ * family with special FPGA custom functionalities.
  * \author Javier Arribas, jarribas(at)cttc.es
  * -----------------------------------------------------------------------------
  *
@@ -14,27 +15,27 @@
  */
 
 
-#ifndef SRC_LIBS_ad936x_iio_custom_H_
-#define SRC_LIBS_ad936x_iio_custom_H_
+#ifndef GNSS_SDR_AD936X_IIO_CUSTOM_H
+#define GNSS_SDR_AD936X_IIO_CUSTOM_H
 
+#include "ad936x_iio_samples.h"
 #include "concurrent_queue.h"
 #include "gnss_time.h"
 #include "pps_samplestamp.h"
 #include <boost/atomic.hpp>
+#include <iio.h>
+#include <ad9361.h>  // multichip sync and high level functions
 #include <memory>
 #include <string>
-
-#ifdef __APPLE__
-#include <iio/iio.h>
-#else
-#include <iio.h>
-#endif
-
-#include "ad936x_iio_samples.h"
-#include <ad9361.h>  // multichip sync and high level functions
 #include <thread>
 #include <vector>
 
+/** \addtogroup Signal_Source
+ * \{ */
+/** \addtogroup Signal_Source_libs
+ * \{ */
+
+
 class ad936x_iio_custom
 {
 public:
@@ -121,10 +122,7 @@ private:
     struct iio_device *dds_dev;
 
     // stream
-
     uint64_t sample_rate_sps;
-
-
     int debug_level;
     int log_level;
     bool PPS_mode;
@@ -144,4 +142,6 @@ private:
     std::thread capture_time_thread;
 };
 
-#endif /* SRC_LIBS_ad936x_iio_custom_H_ */
+/** \} */
+/** \} */
+#endif  // GNSS_SDR_AD936X_IIO_CUSTOM_H
diff --git a/src/algorithms/signal_source/libs/ad936x_iio_samples.h b/src/algorithms/signal_source/libs/ad936x_iio_samples.h
index 63d30545b..53fff2c9e 100644
--- a/src/algorithms/signal_source/libs/ad936x_iio_samples.h
+++ b/src/algorithms/signal_source/libs/ad936x_iio_samples.h
@@ -15,17 +15,21 @@
  */
 
 
-#ifndef SRC_LIBS_ad936x_iio_samples_H_
-#define SRC_LIBS_ad936x_iio_samples_H_
+#ifndef GNSS_SDR_AD936X_IIO_SAMPLES_H
+#define GNSS_SDR_AD936X_IIO_SAMPLES_H
 
 #define IIO_DEFAULTAD936XAPIFIFOSIZE_SAMPLES 32768 * 4
-
 #define IIO_INPUTRAMFIFOSIZE 256
 
 #include <memory>
 #include <stdint.h>
 #include <vector>
 
+/** \addtogroup Signal_Source
+ * \{ */
+/** \addtogroup Signal_Source_libs
+ * \{ */
+
 class ad936x_iio_samples
 {
 public:
@@ -37,4 +41,6 @@ public:
     char buffer[IIO_DEFAULTAD936XAPIFIFOSIZE_SAMPLES * 4 * 4];  // max 16 bits samples per buffer (4 channels, 2-bytes per I + 2-bytes per Q)
 };
 
+/** \} */
+/** \} */
 #endif
diff --git a/src/algorithms/signal_source/libs/ion_gsms_chunk_unpacking_ctx.h b/src/algorithms/signal_source/libs/ion_gsms_chunk_unpacking_ctx.h
index 3c5d7b662..6799f1080 100644
--- a/src/algorithms/signal_source/libs/ion_gsms_chunk_unpacking_ctx.h
+++ b/src/algorithms/signal_source/libs/ion_gsms_chunk_unpacking_ctx.h
@@ -34,8 +34,8 @@ struct IONGSMSChunkUnpackingCtx
     static constexpr uint8_t word_bitsize_ = sizeof(WT) * 8;
 
     const GnssMetadata::Chunk::WordShift word_shift_direction_;
-    WT* iterator_;  // Not owned by this class, MUST NOT destroy
-    WT current_word_;
+    WT* iterator_ = nullptr;  // Not owned by this class, MUST NOT destroy
+    WT current_word_{};
     uint8_t bitshift_ = 0;
 
     IONGSMSChunkUnpackingCtx(
@@ -51,7 +51,10 @@ struct IONGSMSChunkUnpackingCtx
             {
                 iterator_ = &data_buffer[data_buffer_word_count];
             }
-        advance_word();  // Initializes current_word_
+        if (iterator_)
+            {
+                advance_word();  // Initializes current_word_
+            }
     }
 
     void advance_word()