Preamp noise now

Just recently I have moved my equipment from one side of the room to the other. I have noticed a light noise every time I turn up or down the preamp (sounds like a light buzz, preamp volume control motor).

The components are plugged in the same outlets as before, and the same IC's are used.

There is one difference now, I only have one source plugged in, (the Stereolink 1200).

I removed that source and still have the noise.

I used to use the preamp with all of the inputs used up. As well as the video inputs as well. I had no noise.

Is this a load chracteristic?

I will try to hook up other equipment later and load the preamp down and I hope that will fix everything.

The pre-amp is the Parasound Z-pre and the Amplifier is the McCormack DNA-225 with Paradigm Studio Reference 80 speakers and Monster Cable (yuck!) CX-4 Bi-wire cable.
It is actually possible that you have a buzz from inadequate grounding which might have been solved by one of your source components, i.e., the preamp might have been properly grounded before via the interconnect through a properly grounded source component. If so, I suggest you hook everything up like before (as you have indicated already is your intention) and see if the buzz goes away. Good luck.
I have had similar problems in the past that were fixed by replacing unshielded interconnects (Kimber PBJ) with shielded ones. May or may not be your problem but it took me forever to find that solution.