   // show audio muted and debug info.
   sprintf(tempBuf, "AUDIO MUTED: Airspeed to low. Min:%i ASI:%i",MUTE_AUDIO_UNDER_IAS, ASI);
   Serial.println(tempBuf);
+  toneMode = TONE_OFF;
+  return;
 #endif
   }
   


#define TONE_PIN          2     // TIOA0
#define PIN_LED1          13    // internal LED for showing AOA status.
#define PIN_LED2          54    // external LED for showing serial input.
#define TONE1600hz        1600 
#define TONE400hz         400
#define PULSE_TONE        1


// Min airspeed in knots before the audio tone is turned on
// This is useful because if your on the ground you don't need a beeping in your ear.
#define MUTE_AUDIO_UNDER_IAS  25

// dynon expected string length
#define DYNON_SERIAL_LEN      53
