Randall KH75 sound like wet farts HELP

[PowoFR]

Well well well, took me 4 hours to meticulously clean all the jack contacts. I stuck a piece of q-tip in the headphone socket, it took me more than 2 hours to remove it. I had to bend needles it was a nightmare.

Now that all is perfectly clean, I'm rewarded by this:
https://www.youtube.com/watch?v=rmQ-Oj7MkuM

[glebert]

So, it sounds like it isn't a simple fix. You got the amp for cheap, apparently without trying it first. I know it can be frustrating, but at this point you should probably lower your expectations and either cut your losses or decide you are going to try to learn how to fix an amp (which you may or may not be successful at).

[PowoFR]

The speaker already cost more than what I paid.
Maybe with the video someone is going to have another idea. I'm not giving up yet.
The dump is closed until friday.

[glebert]

I had a Randall amp with a similar power amp module, and I found that mine didn't match any of the schematics that I could find. Some were close, but not quite the same. The problem with mine ended up being in the part of the schematic that was different, so I needed to reverse engineer how that part of the amp was supposed to function. The problem with mine was in the "protect" circuit that basically cuts signal to the power section if the amp is being way overdriven.

I would start by comparing your amp to the schematic included earlier and find out if it is the same, different, or kind of the same.