I have a Linn Sondek LP-12 with Valhalla which I just setup for the first time. It came with BNC connectors so I had to get 2 RCA adaptors which fit to the MC of my tube pre-amp.
My question is this; I attached everything on the Linn Sondek to the pre-amp and got significant 60 cycle hum in the phono stage. Even when I disconnect the turntable from the pre-amp I get tremendous hum on the phono stage when turning up the vol. control. There is a very slight hum on CD and Tuner, but not bad and nothing like in phono. Everything goes into a Monster Power 5100 power conditioner. Any suggestions on what is wrong and how I can fix it?
One possibility is that your phono amp is in close proximity of an electric magnetic device - a transformer for example, and is picking up hums from there. Please try to move the phono amp around to see if the situation improves.