yanyan39

Ansil, you were spot on, changed the chip and all is well. Thanks

Thanks for that, will check it out.

Hi I have a Marshall vs100, It's been noisy and unreliable for a while. I've taken it apart and found a capacitor and input jack with multiple cold joints on the preamp board so have fixed those. The amp is now much improved, but there remains a problem on the clean channel, As the volume is increased there is nasty breakup which responds to louder playing. Both distortion chanels are fine so i don't think it's the power amp. I have the schematic and was wondering if this problem could be a faulty TL072 chip in the preamp, any ideas how best to proceed with sorting this. I'm pretty sure there are no more bad joints on the preamp board and I've used contact cleaner and all plugs, sockets, pots and jacks. thanks for any help.