Speaker produces crackling/distorted audio with M5Unified

[chate]

Title: Speaker produces crackling/distorted audio with M5Unified

Environment:

• Arduino IDE: 2.3.10
• M5Stack Board: 3.3.9
• M5Unified: 0.2.22
• Device: M5Stack Basic
• OS: Mac

Issue Description:
When using M5Unified 0.2.22, the speaker produces crackling/distorted audio (buzz)
when playing tones or notes. The same speaker works cleanly with M5Stack.h library,
indicating a problem with M5Unified's speaker driver implementation, not hardware.

My code

#include <M5Unified.h>

// Note frequencies
#define C4 262
#define D4 294
#define E4 330
#define F4 349
#define G4 392
#define A4 440
#define B4 494

#define MSEC_PER_MIN 60000
int melody[] = { G4, G4, G4, D4, E4, E4, D4, B4, B4, A4, A4, G4 };
int noteValues[] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1};
int numNotes = sizeof(melody)/sizeof(melody[0]);

int tempo = 120;  // normal tempo BPM

void setup() {
  // initialize M5Stack and speaker
  M5.begin();
  M5.Speaker.setVolume(64); // 128
  M5.Display.setTextSize(3);
  M5.Lcd.println("Press BtnA to play");
}

void loop() {
  M5.update();
  if (M5.BtnA.wasPressed()) {
    for (int i = 0; i < numNotes; i++) {
      int playTime = (noteValues[i]*(MSEC_PER_MIN / tempo));

      M5.Speaker.tone(melody[i], playTime);
      delay(playTime);
      delay(50);
    }
  }
}

Old Environment:

• Arduino IDE: 2.3.10
• M5Stack Board: 2.1.4
• M5Stack: 0.4.6
• Device: M5Stack Basic
• OS: Mac

Code for old environment:

#include <M5Stack.h>

// Note frequencies
#define C4 262
#define D4 294
#define E4 330
#define F4 349
#define G4 392
#define A4 440
#define B4 494

#define MSEC_PER_MIN 60000
int melody[] = { G4, G4, G4, D4, E4, E4, D4, B4, B4, A4, A4, G4 };
int noteValues[] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1};
int numNotes = sizeof(melody)/sizeof(melody[0]);

int tempo = 120;  

void setup() {
  // initialize M5Stack and speaker
  M5.begin();
  M5.Speaker.setVolume(4);
  M5.Lcd.setTextSize(3);
  M5.Lcd.println("Press BtnA to play");
}

void loop() {
  M5.update();
  if (M5.BtnA.wasPressed()) {
    for (int i = 0; i < numNotes; i++) {
      int playTime = (noteValues[i]*(MSEC_PER_MIN / tempo));

      M5.Speaker.tone(melody[i]);
      delay(playTime);
      M5.Speaker.mute();
      delay(50);
    }
  }
}

Actual Behavior:
Audio produces crackling/distorted sound (buzz) overlaid on the tone. While using old M5Stack board 2.1.4 + M5Stack libary 0.4.6 produces clean, clear audio without any distortion.

Workaround Attempted:

• Reducing volume with M5.Speaker.setVolume(64) - doesn't fix
• Using M5.Speaker.playRaw() instead of tone() - still produces distortion
• Config M5.Speaker

auto cfg = M5.Speaker.config();
cfg.magnification = 8;      
cfg.sample_rate = 44100;    
cfg.dma_buf_len = 256;      
M5.Speaker.setConfig(cfg);

doesn't fix

Please help me how to fix this problem.