ADAU1467 using aux adc for volume

Good afternoon. I made volume control on ADAU1467 in Sigma Studio.

I used:

- 5000 ohm potentiometer.

- AUXADC pin 7 to connect to the potentiometer.

-ADAU1467's pin 9 to get 3.3 volts (also i tried supply power 3.3V)

I have the following problem - the numbers are constantly changing, running around. There are no stable numbers. I used different potentiometers, but the result is the same.How to fix that problem?