Please help with Levinson 380S Proceed

I just bought a ML 380s and a proceed HPA 2. I used good ballanced cabels and running to B&W Nautulus 805. When I turn up the volume with a cd playing or with a cd off, there is a fairly niticable buzz comng from the speakers. Could this be the amp or the pre? I tried switching inputs but it happens with any source. Also when I turn the volume knob at high levels, the increase in volume is not smoothe. each speaker randomly pops up and down volume levels. (very hard to describe) Could this be the amp or the pre? Any help is very appreciated. If there is someone out there who is very experienced with this and can help me please email me so I may be able to describe the problem in further detail. Any help is very much appreciated.
check to see if you amp and preamp is plugged into the same outlet, this can cause a ground loop hum or buzz, try connecting in seperate outlets and see if the buzz goes away, this is a simple solution to a common problem,
Take a step-by-step approach to finding the source.

1) Disconnect pre-amp from power amp (remember to turn things off while changing cables).

2) Turn the power amp back on and see what you get. If you hear the buzz then something's going on with the amp, otherwise on to the next step.

3) Connect the pre-amp but do not connect any sources to it. Turn everything back on. If the buzz appears then it's the pre-amp.

4) Plug cables into the pre-amp but not into the source. If the buzz appears then it's a cable thing - like defective cables or rfi interference.

5) Attach the cables to the source and try again. First without power to the source and then with power. A problem that arises here is probably with the source.

This procedure will usually locate the problem component. Where to go from there depends on what you find.

If you have other components handy you can try swapping them in and see what happens.

Let us know what you find.

- A
Try a set of single ended cables between the pre-and amp just in case you have a problem there. Either with the cables or the balanced outputs from the pre or balanced inputs on the amp. Also make sure the single ended/balanced toggle switches on your hpa2 are fully seated towards the input you want.
Excellent response Aragain! Cheers. Craig