Garbage output from external i2s ADC

[tester]

Hello,

I have connected an external 24bit I2S ADC (CS5341) and I only get random data from the device.

I tried both master and slave mode and different samplerates but I always get random data.

I have checked both the LRCLK and BCLK in master and slave mode and they are present.

This is my initialization code:

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     #define SAMPLE_RATE 192000
     #define PIN_I2S_BCLK 27
     #define PIN_I2S_LRC  26
     #define PIN_I2S_DIN  14
     #define PIN_I2S_DOUT -1

     i2s_config_t i2s_config =
     {
        .mode = i2s_mode_t(I2S_MODE_SLAVE | I2S_MODE_RX),
        .sample_rate = SAMPLE_RATE,                        
        .bits_per_sample = I2S_BITS_PER_SAMPLE_32BIT,
        .channel_format = I2S_CHANNEL_FMT_RIGHT_LEFT,
        .communication_format = (i2s_comm_format_t)(I2S_COMM_FORMAT_I2S | I2S_COMM_FORMAT_I2S_MSB),
        .intr_alloc_flags = ESP_INTR_FLAG_LEVEL1,
        .dma_buf_count = 4,                          
        .dma_buf_len = 512,
        .use_apll = 0,                            
     };
  
     i2s_pin_config_t pin_config;
   
     pin_config.bck_io_num = PIN_I2S_BCLK;
     pin_config.ws_io_num = PIN_I2S_LRC;
     pin_config.data_out_num = -1;//I2S_PIN_NO_CHANGE;
     pin_config.data_in_num = 14;//PIN_I2S_DIN;

     i2s_driver_install(I2S_NUM_0, &i2s_config, 0, NULL);
     i2s_set_pin(I2S_NUM_0, &pin_config);

And the read code:

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uint32_t bytes_read;
uint32_t samples[1024];

void loop()
{
    i2s_read(I2S_NUM_0, (char*)samples, 1024 * sizeof(uint32_t), &bytes_read, portMAX_DELAY);
        
    for (int i = 0; i < 1024; i++)
    {
        uint32_t dat = (samples[i] & 0xFFFFFF);

        Serial.printf("%d : %d\n",i, dat);
    }  
    
    delay(1000);
}

This is what I get as output:

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0 : 81408
1 : 16757248
2 : 2048
3 : 16351104
4 : 75520
5 : 462848
6 : 209408
7 : 16660480
8 : 16750848
9 : 405504
10 : 258816
11 : 16639488
12 : 16770304
13 : 208896
14 : 49152
15 : 16713472
16 : 3840
17 : 16676608
18 : 16712960
19 : 16441088
20 : 112640
21 : 16754176
22 : 16765952
23 : 16289536
24 : 131584
25 : 63616
26 : 16672256
27 : 16277248
28 : 101376
29 : 16415488
30 : 131200
31 : 397184
32 : 16660864
33 : 1102976
34 : 34048
35 : 37120
36 : 9216
37 : 16161152
38 : 128512
39 : 16695296
40 : 16766208
41 : 307968
42 : 29440

I have tried different settings but always get random data at the output. It makes no difference if I set the ADC in master or slave mode. Clock lines matches the samplerate settings. What could be wrong? I`m sure the ADC board works correctly. if I hook the ADC board up to a Raspberry it works fine. I double checked the data and clock lines and they are connected correctly to the ESP32.

If I disconnect the data line from the ADC and connect it to ground the output is 0 and if I connect the data pin to VCC the output is 0xFFFFFF so the data pin is reading its input correctly.

What could be wrong?