What would cause noise (ground noise?) when touching the volume control and tone controls?

tubeguy76

I have a new preamp that I recently hooked up and I'm getting some interference or what may be ground noise but I only hear it when I'm physically touching the metal volume knob and tone controls.

That sounds defective. I'd return it to the dealer for an exchange.

Sounds like a ground loop. Try connecting to ground separately or a grounding box. Does this happen only on phono or also higher voltage inputs?

@cleeds Ah... it's a "new to me" preamp, but it's a used unit.  Fairly new though.

@antigrunge2 I don't have a phono setup, just a streamer connected to a DAC and the DAC connected to the preamp. 

I can reach out to the preamp maker, just wanted to see if I could solve it myself before doing so.  :)