Drivin' me Crazy

Good ideas above.
Per Mosin- gently hold the transformer down to see if it goes away. Could be loose on the chassy.
Check your cartridge connections. If one is loose, remove it and ( a la Fremer) place a tooth pick inside the connector and crimp it closed so it fits snug on the cart pin.
Good luck. Keep us posted.

Thanks folks. Definitely a buzz, not like a 60 cycle hum. Thanks all of you. Sounds more like zzzz than ummmm. When you touch/tap the pre the buzz may crackle then die only to regenerate later, sometimes in seconds, sometimes several minutes later. I have checked my cartridge connections-seems fine. My turntable just recently came back from a tuneup from George Merrill. Before I left there we listened to it through all Quad tube equipment and a Sutherland PH3D for an hour or so and it sounded great. I am technically challenged, so I ask can you touch the transformer with it playing without fear of shock? The transformer on the pre is held to the chassis by a single nut. I assume (yeah I know) it is safe to tighten while unplugged.

I had the same issue with a phono pre. Nothing I could do fixed it and finally sent it in for repair and upgrades. I went through that self fix roller coaster for months, my suggestion if you cannot track it down in a day or two send it in for repair.
good luck!

I'm guessing it is a mechanical transformer buzz. Try tightening the hold down and maybe applying some mortite or other damping compound. These can be difficult to stop.

I tightened the transformers and the power supply and life is indeed better. It is not gone completely but we are on the right track.