It sounds like a noisy pot.
If it has noisy pot, I should hear noise while adjusting the knob even if there is no music playing, also the noise completely disappear when I stop adjusting the knob .Coming from a schiit fulla 2 , I know what noisy pot soundlike and Yes it really seems to be the case ! Haha. Schiit .... ...
Is there a option to fix it ?