if you're downloading FLAC files you can't play them until they're complete.
the way normal downloads work is they start at 1% and progress toward 100%. So if you have 45% of an mp3 for instance then winmx or kazaa will play what you've got before it's complete.
Flac downloads work differently:
when you connect it checks to see who else online has "bits" or "parts" of your download and gets those bits if YOU don't already have them. So in reality a FLAC concert could show on your machine as being 76% complete - but that doesn't mean you have 3/4 of the tracks. What you probably have is a bit of most of the tracks, maybe all of one or two and none of a few...you'll be lucky if anything is playable at this stage in winamp.
Finally once you have a full FLAC concert make sure (as said above) you google for "winamp flac plugin" - because they still won't play without it
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