Marshall G100R CD hum on the overdrive channel

[BadAssJohnny]

Hey. I've got a G100R CD and its developed a problem; there is a 60Hz hum, but only on the distortion channel. This is NOT caused by a single coil pickup. By the time I turn the distortion up to 10 O'clock the 60 Hz hum is there and gets louder the more I turn up the distortion. It didnt use to do this, and it sounds like a filter cap issue but the clean channel has no hum and that puzzles me. If its just some capacitor in the distortion channels power source, please let me know which one it might be. I'd really appreciate it. Thanks alot, -Aaron.

[Enzo]

I'd be more inclined to think it is a bad op amp in the channel.

[BadAssJohnny]

Hey thanks. Do you know where I could get a schematic for it?

[oldDog78]

Hi, i have the same problem with my G100RCD,, you found the cause??

Thanks,,