1994 Fender Ultimate Chorus

[Twinkie2007]

Hello, me and my buddy are having an issue with his 1994 Fender Ultimate Chorus. When we go to band practice and start his amp, it will switch between clean and drive channels, and his Chorus effect goes in and out. Additionally, I also have one of these amps, however mine is a 1995, and operates properly. Our main concern is why does it get so hot after playing for two hours. Mine gets to around the higher 90's in temp, and his gets hot enough to burn you. The only time his '94 has been opened, was a few years ago, by professionals, to have dust cleaned out. I think dust is causing the heating problem, and the switching channels is caused by faulty fuse/wiring, however, I'm not an expert on amps or their components. Any help would be much appreciated.

[The Dude]

Here's the schematic (attached). I would first clean all the jacks. They are switching jacks and could cause intermittent problems. Intermittent footswitch jack could cause intermittent channel switching. Intermittent effect loop jacks could cause intermittent output. This is a stereo amp with stereo chorus, so if one channel is intermittent or not working, it will sound like chorus is not working.

Ultimate Chorus.pdf