I recently bought this beautiful GEM Jumbo 61. I got it pretty cheap because it was not working, when we tested it. I changed the fuse and now it is working, it just has this humming problem which I think is related to the bass section.
The humming is pretty loud only if you turn on the lower keys (balance). It becomes pretty loud if you push one of the lower keys but it randomly gets quieter if you push on of the keys again. Also if you turn the percussion sound on and play it in the lower keys it will become quieter over time and then the volume will go up again.
For better understanding I made a video of what is happening:
Does anyone have an Idea what could cause the problem and how I could get rid of it?
I would love to have this organ working properly because the sound is just awesome.