Marshall TSL602 Channel Switch cracking

[Hubaer]

Hello together,

I have a problem with a Marshall JCM 2000 TSL602. When I switch from OD1 or OD2 to the clean channel I got a short crack that I can hear loud out of the speakers. It does not matter if I get the footswitch or put it out and take the switches in front of the amp - it allso cracked when I go back to clean.

I got the schematics and look for the problem. In my oppinion there are 2 places to look, the relais who are switching the sound or arround the mosfets who bring the signal to ground.

Have had anyone the same problem or has a solution for the problem ?

Thank you

Ingo

[g1]

Possibly one of the mosfets is supposed to cut (mute) the sound while the relay switches, and is not doing it's job.

[Enzo]

JFETs...

Also check that none of the signal path ICs have a DC offset at an output pin.