Probably a dumb question, but are your front speakers offering the same load as the rears (i.e., are both pairs 8-ohm or are the fronts 4-ohm units while the rears are 8)? If so, the fronts will play much louder (assuming speaker efficiency is about the same).

Actually its uncommon to find non-8-ohm consumer home speakers, but it does happen. Also, only the most robust amps bode well with mismatched speaker loads.

And as previously mentioned, most HT recievers have a way to adjust signal levels to each speaker in the system...still, there is little to no signal in stereo mode, and as rear fill, very dependent on the encoded DVD material, be it Dolby, DTS, or THX.

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