I hear it with a USB connection to the PC and almost always without one as well. The problem is that I want to make short recordings with it, and regardless of whether you hear the clicking or not (with or without USB), it’s always on the recording and clicks according to a specific pattern. That’s why I first thought it might be I2C or the serial monitor, but even a completely empty code produces the clicking. Even when I flash the latest firmware via M5Burner and run the program. You can’t hear it that way, but it’s always present in the audio recording.
External Port Power is set to INPUT. With OUTPUT, you get very loud noise.

It clicks about 11 times (lasting approx. 2 seconds) at regular intervals, with a 1-second pause until the next click pattern.
The image shows an amplified recording. It is recorded in AMR format. However, it also occurs in WAV and as a binary (raw) array.
The vertical lines are these clicking noises that are always present in the pattern.

Is it due to the S3 or the hardware??