Why does a noise occur at regular intervals when the UAC equipment records and plays?

[a_ziliu]

During UAC recording and playback, if the microcontroller (MCU) and the host clock frequency error occurs, the error will be amplified with time, resulting in MCU USB upload / download buffer overflow. Therefore, a noise occurs.
This can be solved by dynamically adjusting the clock frequency of the audio Codec according to the state of the buffer to prevent the occurrence of overflow events.