Id say you are having trouble with your codecs.
i recently downloaded a movie file and this helpful little brief was included:
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Troubleshooter
If you are having issues with this release, jittery image, no sound or anything like that, it is with 99.9%
certainty that you are having issues with your CODECS. It doesn't matter which player you use, as long as
the codecs needed to play this file aren't installed on your computer. It's extraordinarly rare that a movie
downloaded with BitTorrent is broken and/or can't be played back with the right software. Some experience
that that Windows Media Player tries to download a codec, for instance, and give you an error. This is not
a faulty rip, it's a weakness in that player, not having access to the proper codec.
There is only one player that doesn't require any system codecs (uses its own) and that's: Videolan (VLC)
This player also works on several plattforms, including Mac OS X. However, it will reduce some of the quality
of the movie when viewing it, unfortunately. Otherwise an excellent compromise if you don't want to down-
load any codecs.
You can tell by the name of the movie that you have downloaded, which codec is required. For instance,
Name_Of_The_Movie_AC3_Xvid_[ReleaseGroup].avi AC3 is the audio codec, and Xvid is the encoder
(codec) for the movie. There are also movies encoded with DivX, in which case the filename would reveal that,
as in it being Name_Of_The_Movie_DivX_[ReleaseGroup].avi instead. You'll find many other releases
named in this fashion.
.avi is simply a container format. Like a container, an .avi file can contain a wide variety of codecs, therefore
it's common that one .avi file works, and another doesn't. This is why you have to find out which codec was
used when the avi-file was created.
GSpot is an excellent tool for finding out if you have the required codecs installed. Now, it happens that some
people have installed various codec packs, and/or individual codecs as well as players installing codecs without
your knowledge. This tool will provide you with information on the various codecs you have installed on your
computer. Simply open the file with GSpot and it will determine if you have the codecs necessary for playback.
It can also show you a list of all audio and video codecs currently installed on your system (click View, then
Installed codecs.)
We recommend that you avoid all codec packs.
They tend to install unnecessary components that can lead to conflicts. Often you will find that with too many
codecs installed you experience bad playback (jittery, out of sync, etc.) The best way to solve this problem is
to first remove all codecs from your system. Then install the individual codecs as necessary to play back the
files that you encounter.
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