Thanks for your reply.
I am leaning towards a new receiver because the Marantz I have is getting old and it would nice to have native TrueHD and DTS-HD since my current only does HD audio via PCM. Either way, my budget is firm but anything has got to push more power than my old Marantz.
How can I tell if the speakers are damaged...? I am a bit scared now.
TV: Panasonic Plasma 60" TC-P60ST30
Receiver: Pioneer SC-1222-K
Blu-Ray: Sony BDP-S590
Speakers: MK Sound M-7 / M4-T
Sub: MK Sound SB-12