diff --git a/radio/src/gui/212x64/radio_diagkeys.cpp b/radio/src/gui/212x64/radio_diagkeys.cpp
index 7a9f42499..56b8d102c 100644
--- a/radio/src/gui/212x64/radio_diagkeys.cpp
+++ b/radio/src/gui/212x64/radio_diagkeys.cpp
@@ -45,7 +45,7 @@ void menuRadioDiagKeys(event_t event)
     displayKeyState(5 * FW + 2, y, i);
   }
 
-  for (uint8_t i = 0, cnt = 0; i <= NUM_SWITCHES; i++) {
+  for (uint8_t i = 0, cnt = 0; i < NUM_SWITCHES; i++) {
     if (SWITCH_EXISTS(i)) {
       div_t qr = div(cnt++, 6);
       coord_t x = 4 * FH * qr.quot;
diff --git a/radio/src/gui/480x272/radio_diagkeys.cpp b/radio/src/gui/480x272/radio_diagkeys.cpp
index c952775a9..9e26ebe86 100644
--- a/radio/src/gui/480x272/radio_diagkeys.cpp
+++ b/radio/src/gui/480x272/radio_diagkeys.cpp
@@ -61,7 +61,7 @@ bool menuRadioDiagKeys(event_t event)
     displayKeyState(70, y, i);
   }
 
-  for (uint8_t i = 0; i <= NUM_SWITCHES; i++) {
+  for (uint8_t i = 0; i < NUM_SWITCHES; i++) {
     if (SWITCH_EXISTS(i)) {
       coord_t y = MENU_HEADER_HEIGHT + 1 + FH * i;
       getvalue_t val = getValue(MIXSRC_FIRST_SWITCH + i);