Problems with rk3308 internal codec

Hi,

I’m designing a product based on Radxa Rock pi S SOM module and I’ve found an issue with the internal codec of RK3308.

Sometimes, the ADC part of the codec gets bad initialized and It gives a lot of noise, and with louder volume.
Looking at the codec registers, I get the same values in both cases: good sound- bad sound.

I simply produce the issue by running this command some times:

arecord -d3 -c 1 -r 48000 -f S24_LE -D plug:linein1 | aplay -D plug:chan12

where linein1 are the 4 and 5 channels of rk3308 acodec ADC and chan12 are two channels of my external i2s amplifier.

Could anyone help me?

Thank you,
miguel