Esp32 und PCM510x Mute Problem

Hier folgt der zuletzt verwendete Code:

#include <driver/i2s.h>

#include <math.h>

#define I2S_BCK  33

#define I2S_LCK  14  

#define I2S_DIN  32

#define SAMPLE_RATE 44100

#define AMPLITUDE   16000  

void setup() {

  Serial.begin(115200);

  delay(1000);

  i2s_config_t i2s_config = {

    .mode = (i2s_mode_t)(I2S_MODE_MASTER | I2S_MODE_TX),

    .sample_rate = SAMPLE_RATE,

    .bits_per_sample = I2S_BITS_PER_SAMPLE_16BIT,

    .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,

    .communication_format = I2S_COMM_FORMAT_STAND_I2S,  

    .intr_alloc_flags = 0,

    .dma_buf_count = 8,

    .dma_buf_len = 64,

    .use_apll = false,

    .tx_desc_auto_clear = true,

    .fixed_mclk = 0

  };

  i2s_pin_config_t pin_config = {

    .bck_io_num = I2S_BCK,

    .ws_io_num  = I2S_LCK,

    .data_out_num = I2S_DIN,

    .data_in_num = -1

  };

  esp_err_t err;

  err = i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);

  Serial.printf("i2s_driver_install: %d\n", err);

  err = i2s_set_pin(I2S_NUM_0, &pin_config);

  Serial.printf("i2s_set_pin: %d\n", err);

  err = i2s_set_clk(I2S_NUM_0, SAMPLE_RATE, I2S_BITS_PER_SAMPLE_16BIT, I2S_CHANNEL_STEREO);

  Serial.printf("i2s_set_clk: %d\n", err);

  Serial.println("PCM510x Testton 440Hz startet...");

}

void loop() {

  static float phase = 0;

  int16_t sample[2];

  float s = sin(phase) * AMPLITUDE;

  sample[0] = sample[1] = (int16_t)s;

  size_t bytes_written;

  i2s_write(I2S_NUM_0, sample, sizeof(sample), &bytes_written, portMAX_DELAY);

  phase += 2.0 * M_PI * 440.0 / SAMPLE_RATE;

  if (phase > 2.0 * M_PI) phase -= 2.0 * M_PI;

}