XMovie is a versatile multimedia and DVD player.
XAnim didn't play stereo sound and MTV was a $15 shareware. Hard to believe how today's applications toss movies around like nothing when just 4 years ago it was an ordeal just to play an MPEG stream.
XMovie is mainly intended for uncompressed movie playback, nonstandard output from Cinelerra, and testing decoder libraries.
It's not intended for low resolution, low bitrate internet downloads. Your luck will improve with something like M Player
6 channels of audio can be sent to a soundcard supporting 6 channel audio. More importantly, HDTV program and ATSC transport streams play back.
These streams are usually obtained through a capture board like the WinTV HD, set top box hacking, or other means. Forget about downloading HDTV moviez from the internet.