Peavey Mace VT head

[lhowell2810]

I just found a Peavey Mace VT head and bought it. The clean channel sounds great! But, the effects channel fades normal to flat. Even if I turn the phaser off it is still drifting solid bass to sounding like you are playing it through a small speaker with no bass and sounds very then. Has anyone had an issue like this before? Or does anyone have any idea where to start to trouble shoot?

I have tried it from just the pre-amp and it does the same so it would be in the pre-amp part but these amps are solid state so not sure where to start. It had been sitting for a while and I had to use tuner cleaner on the inputs and that cleared up that issue of fade on all channels. I was wondering if the pots needed to be cleaned as well but that is a much bigger job to take it apart so I thought I would see if anyone had any suggestions as to what would cause the effects channel to go from full sound to flat?

I'm new here so forgive me for anything I may have done worng.

[Enzo]

I would aapply a signal and use a signal tracer to follow it through the channel. With a meter I would make sure my power supplies were right in the preamp section, and I would be checking op amp outputs for unwanted DC offset.