The problem is, that the sound is disturbed by frequent, regularly tic-sounds. This happenes with radio stations <=128000 bit/s (MP3).
Yes, it is an I2S connection between two ESP32.

Thanks for the link to the discussion.
Unfortunately, there seems to be no solution for this issue. It seems to be a bug the I2S receiver.
BTW:
Why does a the slave (receiver) needs to have a sample frequency on a synchronous clock driven bus at all? Reading in the data could be realized with a two simple shift registers, selected by ws_pin as DACs will probably do it. If we do not have a clock line, we have to know the frequency like baudrate on asynchonous UARTs.

I investigated a litte bit more, the result is:
The samplerate from the incoming I2s stream has always to be converted to 44100, because the A2DP output seems to be fixed at this bitrate. The tic-sound were buffer overflows, because of the difference between 48000 (i2s in) and 44100 (A2DP out).
I use as mentioned before a webradio streamer s a source on a separate ESP32 and the sample rate of the output depends on the quality of the web radio station. This is no problem when using a DAC like PCM5102 at all.
I saw a sample about resampling but I did not manage it work for my purpose.
I need I2S (48000) -> resample -> 44100 -> A2DPSource.
I viewed a lot of examples, I do not understand the differences between them fully. Sometimes you use a copier, sometimes not. The arguments of the constructors are not self-explaining (for me) and how the objects are to be used together.
Is there something like a general manual how to use the library?

Thanks in advance

What's wrong with the Wiki ?

Nothing wrong with it. It is well explained but covers the basics only.
The difference might be, that you work on these codes for years and I for three days.
I do not understand, why in the resample example there is not copier.copy() instruction.

Hi Prog32aw, How you solved this can you share your code please

What do you mean?

ESP32->I2S->ESP32 ?

Hello [Prog32aw],
As Wi-Fi and BT not work together hence this logic of using two ESP32. meaning for example Wi-Fi URL fetch at one ESP32 outputting I2S (TX) data to another I2S(RX) ESP32 which works Bluetooth bridge for A2DP output .

What do you mean?

ESP32->I2S->ESP32 ?

Are you still sending audio from one ESP32 to another using an I2S connection between them? If so and it's working can you please share your code with us?

как Вам это удалось? я разработал устройство с экраном и кнопками, может сканировать устройства и записывать их в память, 4 устройства на выбор с возможностью их заменить. но тоже мучает вопрос с низким битрейтом.