TERRIBLE noise with basic sine wave example on XIAO ESP32 C6

[BorisBrock]

I have a XIAO ESP32C6 + a MAX98357 I2S Amplifier board. I uploaded this sine wave example to it (with minor modifications):

#include <Arduino.h>
#include "AudioTools.h"

AudioInfo info(44100, 1, 16);
SineWaveGenerator<int16_t> sineWave(32000);    // subclass of SoundGenerator with max amplitude of 32000
GeneratedSoundStream<int16_t> sound(sineWave); // Stream generated from sine wave
I2SStream out;
StreamCopy copier(out, sound); // copies sound into i2s

// Arduino Setup
void setup(void)
{
  I2SConfig config = out.defaultConfig(TX_MODE);
  config.copyFrom(info);
  config.pin_ws = 3;   // LRC
  config.pin_bck = 2;  // BCLK
  config.pin_data = 1; // DIN
  out.begin(config);

  // Setup sine wave
  sineWave.begin(info, N_B4);
}

// Arduino loop - copy sound to out
void loop()
{
  copier.copy();
}

The result is rather interesting 😉 I get a ultra loud terrible noise from the speaker, which sounds nothing like a sine wave (more like a broken vintage radio).

So I guess I must be doing something fundamentally wrong... Can anyone help?

[pschatzmann]

Not sure what the MAX39857 would be: google does not provide any information.

Did you read the Wiki about DACs ?
My guess would be that you just provide the wrong i2s_format.

[BorisBrock]

Ah sorry, that was a typo. It is a MAX98357: https://learn.adafruit.com/adafruit-max98357-i2s-class-d-mono-amp/overview

From what I found out 44100 Hz and 16 Bits should be fine. Or is there some other relevant setting?

PS:
I also tried config.i2s_format = I2S_LSB_FORMAT, but that did not change anything.

[WimRoose]

I also had some troubles getting a decent result with a MAX98357 - with the gain pin not connected, and config.i2s_format = I2S_LSB_FORMAT, it runs fine now. You could also test generating the sine with sineWave(6000) - when I had the gain pin connected to achieve +3dB gain, this seemed to be the max I could get before the sound really got distorted.