diff --git a/radio/src/inactivity_timer.cpp b/radio/src/inactivity_timer.cpp
index af1c164d9..ba08faf29 100644
--- a/radio/src/inactivity_timer.cpp
+++ b/radio/src/inactivity_timer.cpp
@@ -20,6 +20,7 @@
  */
 
 #include "inactivity_timer.h"
+#include "hal/adc_driver.h"
 #include "opentx.h"
 
 void inactivityTimerReset(ActivitySource src)
@@ -48,17 +49,17 @@ void inactivityTimerReset(ActivitySource src)
   inactivity.counter = 0;
 }
 
-#define INAC_STICKS_SHIFT   6
+#define INAC_STICKS_SHIFT   7
 #define INAC_SWITCHES_SHIFT 8
 
 bool inactivityCheckInputs()
 {
   uint8_t sum = 0;
 
-  for (uint8_t i = 0; i < MAX_ANALOG_INPUTS; i++)
+  for (uint8_t i = 0; i < adcGetMaxInputs(ADC_INPUT_ALL); i++)
     sum += anaIn(i) >> INAC_STICKS_SHIFT;
 
-  for (uint8_t i = 0; i < MAX_SWITCHES; i++)
+  for (uint8_t i = 0; i < getSwitchCount(); i++)
     sum += getValue(MIXSRC_FIRST_SWITCH + i) >> INAC_SWITCHES_SHIFT;
 
 #if defined(IMU)