Zak, did the new driver help? I just got my version 2 amp installed in my 600. and i have the same "underwheliming" experience. The 600 use to be a freaking raw beast, now its like a neutered beast...

I am going to call Axiom. I may end up returning my V2 amp and getting my V1 repaired.. I will wait and see...

Zak, did you take any comparison photos of the back of the amp side by side. It seems like the transformer on the V2 amp is MUCH smaller than the V1's?