Yes, the turntable was made in 1985 and it is a decent one, if not the problem that I am having.

My pre-amp has only two input channels and two output channels, nothing else, and it is specifically a phono (turntable) pre-amp. Unfortunately, I do not have another pre-amp, but this one is fine. I tried running other devices through it and there was no hum.

I did check the continuity of the grounding wire from the RCA to the ground on the chassis and it is fine.

Yes, I am to troubleshooting the problem.

Thanks for helping!