diff --git a/src/open9x.cpp b/src/open9x.cpp
index 8f9895594..1785c0bd2 100644
--- a/src/open9x.cpp
+++ b/src/open9x.cpp
@@ -700,7 +700,7 @@ int16_t getValue(uint8_t i)
 #if defined(EXTRA_3POS)
   else if (i<MIXSRC_3POS2) return (switchState(SW_ID3) ? -1024 : (switchState(SW_ID4) ? 0 : 1024));
 #endif
-  else if (i<MIXSRC_LAST_CSW) return __getSwitch(SWSRC_THR+i+1-MIXSRC_SW1) ? 1024 : -1024;
+  else if (i<MIXSRC_LAST_CSW) return __getSwitch(SWSRC_THR+i+1-MIXSRC_THR) ? 1024 : -1024;
 #endif
   else if (i<MIXSRC_PPM1+NUM_CAL_PPM) return (g_ppmIns[i+1-MIXSRC_PPM1] - g_eeGeneral.trainer.calib[i+1-MIXSRC_PPM1])*2;
   else if (i<MIXSRC_LAST_PPM) return g_ppmIns[i+1-MIXSRC_PPM1]*2;