just been playing a dvd on my stereo upstairs, and it has a THX test where it plays through all the 5.1 speakers. when the test gets to the main left and right speakers the same sound seems to come out the rear speakers, just quiet. with the middle speaker, the rears are silent. my dad thinks its leaking, but i think thats right cos isnt that how surround sound works with just 2.0 stereo? otherwise the 5.1 seems to work fine.

It depends how the test is set up. If the surround test is using true DVD audio, DTS, or Dolby Digital, then you should have descrete sounds coming from each channel. If it is just a stereo signal then depending on your surround emulation you will hear different sounds coming from the back. If you are Using Dolby Pro Locig II, you should hear different sounds from the rear channels, they shouldn't be the same. If there is a mono signal present in the test, it should come from the center channel.

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