XIAO ESP32C3 and I2S. How to?

Hi. Compiled this code again yesterday and it works fine for me. I am using a PCM5102 i2s board rather than the MAX …

/*
 * seeed_esp32_tone2 (SimpleTone from I2S library)
 This example generates a square wave based tone at a specified frequency
 and sample rate. Then outputs the data using the I2S interface to a
 MAX08357 I2S Amp Breakout board.

 I2S Circuit:
 * Arduino/Genuino Zero, MKR family and Nano 33 IoT
 * MAX08357:
   * GND connected GND
   * VIN connected 5V
   * LRC connected to pin 0 (Zero) or 3 (MKR), A2 (Nano) or 25 (ESP32)
   * BCLK connected to pin 1 (Zero) or 2 (MKR), A3 (Nano) or 5 (ESP32)
   * DIN connected to pin 9 (Zero) or A6 (MKR), 4 (Nano) or 26 (ESP32)

 DAC Circuit:
 * ESP32 or ESP32-S2
 * Audio amplifier
   - Note:
     - ESP32 has DAC on GPIO pins 25 and 26.
     - ESP32-S2 has DAC on GPIO pins 17 and 18.
  - Connect speaker(s) or headphones.

 created 17 November 2016
 by Sandeep Mistry
 For ESP extended
 Tomas Pilny
 2nd September 2021
 */
//  These pins work for XIAO esp32c3 and esp32s3
 
#define PIN_I2S_FS      2  //LCK - Word Select
#define PIN_I2S_SCK     3  //BCK - Bit Clock
#define PIN_I2S_SD_OUT  4  //DIN - Data stream
#define PIN_I2S_SD      4

#include <I2S.h>

const int frequency = 440; // frequency of square wave in Hz
const int amplitude = 500; // amplitude of square wave
const int sampleRate = 8000; // sample rate in Hz
const int bps = 16;

const int halfWavelength = (sampleRate / frequency); // half wavelength of square wave

short sample = amplitude; // current sample value
int32_t rightleft;  // sample right and left channels
int count = 0;

i2s_mode_t mode = I2S_PHILIPS_MODE; // I2S decoder is needed
// i2s_mode_t mode = ADC_DAC_MODE; // Audio amplifier is needed

// Mono channel input
// This is ESP specific implementation -
//   samples will be automatically copied to both channels inside I2S driver
//   If you want to have true mono output use I2S_PHILIPS_MODE and interlay
//   second channel with 0-value samples.
//   The order of channels is RIGHT followed by LEFT
//i2s_mode_t mode = I2S_RIGHT_JUSTIFIED_MODE; // I2S decoder is needed

void setup() {
  Serial.begin(115200);
  delay(5000);
  Serial.println("I2S simple tone");
  Serial.println(__DATE__);
  Serial.println(__TIME__);
  Serial.println(__FILE__);
  Serial.println(PIN_I2S_FS);   //     D0  gpio02 //LCK - Word Select
  Serial.println(PIN_I2S_SCK);  //     D1  gpio03 //BCK - Bit Clock
  Serial.println(PIN_I2S_SD_OUT);  //  D2  gpio04 //DIN - Data stream
  Serial.println(PIN_I2S_SD);   //     D2
  Serial.println(sizeof(short)); //  check the num of bits in short integer.

  // start I2S at the sample rate with 16-bits per sample
  
  I2S.setAllPins(PIN_I2S_SCK, PIN_I2S_FS, PIN_I2S_SD, PIN_I2S_SD_OUT, -1);
  if (!I2S.begin(mode, sampleRate, bps)) {
    Serial.println("Failed to initialize I2S!");
    while (1); // do nothing
  }

  Serial.println("Starting tone generation");
}

void loop() {
    if (count % halfWavelength == 0 ) {
      // invert the sample every half wavelength count multiple to generate square wave
      sample = -1 * sample;
    }

    if(mode == I2S_PHILIPS_MODE || mode == ADC_DAC_MODE){ // write the same sample twice, once for Right and once for Left channel
      rightleft = sample;           // right channel
      rightleft = rightleft << 16;
      rightleft += sample;          // left channel
      I2S.write(rightleft);
    }

    // increment the counter for the next sample
    count++;
}