Kustom K-100 garbled distortion

[fester gomez]

howdy all, i have a question about a Kustom K-100 solid state amp...it has been "serviced" by a tech in the area and it emits a clean sound when the guitar is gently strummed, as soon as you hit the strings hard it has the most non-musical garbled distortion you could imagine. The tech replaced just about every transistor, i'm curious about the 50 year old electrolytic 2500uf@50v capacitors. They measure out ok but....any help would be appreciated! thanks

[The Dude]

Since there are several revisions and different schematics of that model, it would help if you post a schematic of YOUR amp.