Have you tried playing with your center image from the mains?
Forget what it's called, though it's a phantom center setting on all AVRs.

Another thing may be the polarity check your wires are in correct orientation, red black match up. You can also set the proper phasing with a 9volt battery. Connect the opposite end of speaker wire to 9volt make sure the woofers move outwards.

I myself have a VP160 you should have more than enough center, to negate the phantom setting.