T4.0 + audio shield revD headphone distortion ?

[emmanuel63]

Hello,
I notice some pretty bad distortion from audio shield headphone output, when setting the volume at low level.
Please compare this to sketches and tell me if you notice the difference.

sketch 1 => distortion

#include <Audio.h>
#include <Wire.h>
#include <SPI.h>
#include <SD.h>
#include <SerialFlash.h>

// GUItool: begin automatically generated code
AudioSynthWaveform       waveform1;      //xy=303.3333333333333,256.6666666666667
AudioOutputI2S           i2s1;           //xy=553.8888702392578,258.3333511352539
AudioConnection          patchCord1(waveform1, 0, i2s1, 0);
AudioConnection          patchCord2(waveform1, 0, i2s1, 1);
AudioControlSGTL5000     sgtl5000_1;     //xy=80.0000114440918,35.555580139160156
// GUItool: end automatically generated code



void setup() {
   AudioMemory(20);   
  sgtl5000_1.enable();
  sgtl5000_1.volume(0.1);
  waveform1.begin(1, 200, WAVEFORM_SINE);
}

void loop() {

}

sketch 2 = no audible distortion

#include <Audio.h>
#include <Wire.h>
#include <SPI.h>
#include <SD.h>
#include <SerialFlash.h>

// GUItool: begin automatically generated code
AudioSynthWaveform       waveform1;      //xy=303.3333333333333,256.6666666666667
AudioOutputI2S           i2s1;           //xy=553.8888702392578,258.3333511352539
AudioConnection          patchCord1(waveform1, 0, i2s1, 0);
AudioConnection          patchCord2(waveform1, 0, i2s1, 1);
AudioControlSGTL5000     sgtl5000_1;     //xy=80.0000114440918,35.555580139160156
// GUItool: end automatically generated code



void setup() {
   AudioMemory(20);   
  sgtl5000_1.enable();
  sgtl5000_1.volume(0.5);
  waveform1.begin(0.1, 200, WAVEFORM_SINE);
}

void loop() {

}

Thank you
Emmanuel