I also cannot get 5.1 channel surround in Vista using any program like Media Player and iTunes, but they get sound during the tests.
When having XP (media center and pro) when playing a 2.1 (stereo) source, the sound would come out of all my speakers. this includes low quality vids and music.
Recently updating my pc with Vista, i found myself drowning in 2 speaker sound (not even a bass speaker unless i set my speaker to stereo which would then come out of front left/right and bass but no surround). If anyone knows of a setting change which could make stereo sound come out of all speakers or a program which would do this without affecting 5.1 sources then drop me a line on here. cheers

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