Hi Folks- I'm working on restoring an old Audiotronics record player to listen to some Recordio 78rpm home recordings I came across, and I need some guidance. When I got it, it made barely any sound. I looked the components over and found two big electrolytic caps that were leaking, and replaced them. That helped a lot. As did replacing the ceramic cartridge and needle. I get decent sound out of it now, but it also has a loud, low hum that doesn't respond to the volume control--it's always the same (loud) volume.I have poked around looking for something obvious--a loose wire, bad ground, damaged component--but nothing is jumping out at me. What might be my next move? Any suggestions are welcome, as I do have a little experience with this sort of thing, but am no means an expert... Thank you!