I'm trying to emulate the effect of doppler shift using audio library on teensy 3.2 and PropShield but am having trouble trying to figure out if it is possible to do with just the audio library itself or if I need to figure out another way to implement it with audio. Not real good with audio library since I've just started doing audio stuff with arduino/teensy just recently so any help/pointers would be appreciated.

Consider this: Using Audio System Design Tool

// GUItool: begin automatically generated code
AudioSynthWaveformSine   hum_sine;       //xy=125,120
AudioSynthWaveformSineModulated hum_sine_fm;    //xy=308,120
AudioSynthWaveform       buzz_waveform;  //xy=308,245
AudioMixer4              mixer1;         //xy=484,194
AudioOutputAnalog        dac1;           //xy=665,194
AudioConnection          patchCord1(hum_sine, hum_sine_fm);
AudioConnection          patchCord2(hum_sine_fm, 0, mixer1, 0);
AudioConnection          patchCord3(buzz_waveform, 0, mixer1, 1);
AudioConnection          patchCord4(mixer1, dac1);
// GUItool: end automatically generated code
Would like to doppler shift what comes out of the mixer. Anybody have an idea on how to do this?