You don't want to switch to stereo with the bypass button. Use the Stereo button just under it on the remote and cycle through to plain stereo (past 7-channel and 5-channel.) [Frankly, you must ALSO have analog audio connected from your DVD player, otherwise you wouldn't hear ANYTHING in Bypass mode.]
Also be sure that in your setup, you have told the system that you DON'T have a subwoofer or surround speakers.
If you're only watching monaural movies -- that is they don't have multichannel or stereo soundtracks -- you ARE ONLY going to hear sound through the center channel.
Also doublecheck your DVD player's setup screens to make sure it's consistent with your speaker setup.
[This message has been edited by boblinds (edited April 04, 2004).]