I would first of all have your 80's set to "small" and 60 or 80hz crossover on your receiver. I don't think that is your problem, but for HT that is what you want to follow THX standards. Have you calibrated all your speakers to the same SPL. Also, have you verified you don't have your speaker wires crossed + and - wrong?

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
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