Levinson turn-on thump... normal??

My dealer let me borrow one of his Levinson 431's (I am ampless at the momeny - looong story) to play with for the weekend.

I noticed that when I take it out of stand-by there is a horrible turn-on thump that comes through the aerials. This happens even when there are no single ended connectors attached (ie no input thumps which could be coming from my Unidisk pre-amp). It's really unpleasant and I'm afraid it's going to damage the 10T's. Is this normal with Levinson gear? I certainly didn't expect it.

I am using a single pair of speaker terminals which are firmly snugged down under the binding posts.

Another thing I noticed was that after the thump the woofer stayed in the "out" position. Not completely pushed out - but further out than it's typical "resting" position (amp off). It seems to only happen on one of the Aerials. I switched to the other channel of the Levinson and it still did it. Any ideas? Is it possible that the resting state is not the "neutral" position of the voice-coil?

Other than those two oddities I am in love with this thing. It really creates a 3 dimensional sound and everything just sounds "right". Bass response is absolutely stunning.

Thanks in advance.