diff --git a/menus.cpp b/menus.cpp
index 62e73278..6cfabe68 100644
--- a/menus.cpp
+++ b/menus.cpp
@@ -516,8 +516,10 @@ void showChangeMode() {
   dialog::addBoolItem(XLAT("racing mode"), racing::on, 'R');
 #endif
 #if CAP_ARCM
-  dialog::addBoolItem(XLAT("dual geometry mode"), dual::state, 'D');
-  dialog::add_action([] { dialog::do_if_confirmed([] { restart_game(rg::dualmode); }); });
+  if(multi::players == 1) {
+    dialog::addBoolItem(XLAT("dual geometry mode"), dual::state, 'D');
+    dialog::add_action([] { dialog::do_if_confirmed([] { restart_game(rg::dualmode); }); });
+    }
 #endif
 #if CAP_DAILY
   dialog::addBoolItem(XLAT("Strange Challenge"), daily::on, 'z');
diff --git a/shmup.cpp b/shmup.cpp
index 86732fd7..cb9d86a1 100644
--- a/shmup.cpp
+++ b/shmup.cpp
@@ -473,7 +473,7 @@ void showConfigureMultiplayer() {
     string s = player_count_name(i);
     if(i <= players) s += dsc(i-1);
     dialog::addBoolItem(s, '1', i == multi::players);
-    dialog::add_action([i] {
+    if(!dual::state) dialog::add_action([i] {
       dialog::do_if_confirmed([i] {
         stop_game();
         players = i;