Beolab Penta/ Beolab 150 problems

Hello all,

I have recently beolab penta mk2 and there seems to be a few problems regarding sound levels and noise. I have the pair of labs connected to my bv732 via power link. The problem is that the sound levels constantly change, sometimes I can barely hear anything, then boom it's too loud. There also seems to be some digital noise commig through. Which can make the top end sound like its underwater.

I have tried various combinations of input levels and bass levelling but the issues remain.

I had some penta vox's attached via a non b&o amp before and thy sounded perfect so I know the tv output is good. The problem also happens when I attach an iPod to the line in on the speakers. Is this a common thing with the beolab 150 amplifier?

Any help would be greatly aprechiated!!