Mtx

[Hexhclass]

This amp plays audio but every time I adjust the gain it will cause the speaker to pull in and out.I bypass the That 2155 IC but problem still there.

Any suggestions?

 

[Perry Babin]

Is there more than a tiny fraction of a volt of DC on the outputs of any of the op-amps?

It appears that you have D199 (cathode connected to the shields) in the circuit. Leave it out. It will let the amp try to ground through the RCA shields if the amp loses its primary ground.