Fender Ultimate Chorus issues

[koosh]

hello a friend has asked me to look at his fender ultimate chorus SS amp.

diagnosis was that Input 1 was not working
Channel 1 is giving low volume. Channel 2 was working fine.

I replaced the input 1 jack and now its working
I also replaced the 2 4700UF 50v capacitors however channel one is still giving low volume and now the amp is cutting off after a couple minutes use. A few minutes later it will be able to power back up.

confirmed fuse is still in tact and heat sink is back in place.
any advice on where to go from here or any troubleshooting steps or common causes for channel 1 to be out?
All solder points look ok and nothing visually obvious. Turning the channel 1 eq pots seem to momentarily flicker the channel back in to use but i've used detox cleaner on them but hasn't made a difference

thank you in advance.

[52 Bill]

Make sure that the metal bar that sits between the heatsink strip and the chassis is correctly seated or else the heatsink will not be able to conduct away the heat and the thermal breaker will cycle on and off like that.

If turning the pots on the clean channel will bring back the sound, either they are still dirty or they may have come apart or the resistance element may be broken or they may have cold solder joints.

There is a mute fet that turns off the channel, but turning the pots would not cause that to change.

[koosh]

Make sure that the metal bar that sits between the heatsink strip and the chassis is correctly seated or else the heatsink will not be able to conduct away the heat and the thermal breaker will cycle on and off like that.

If turning the pots on the clean channel will bring back the sound, either they are still dirty or they may have come apart or the resistance element may be broken or they may have cold solder joints.

There is a mute fet that turns off the channel, but turning the pots would not cause that to change.

Thank you! I suspected the heat sink may be the issue with it cutting off. I will go back and double check that it's re-assembled correctly.
I've also ordered some additional replacement 50k snap in pots. Hopefully replacing these will get the amp working again.