So I did playback for a Christmas dance recital with files provided on a flash drive. Skipping past the awful quality of most of the tracks, one title in particular had a strange little quirk. When looking at the properties of the file, it showed a length of 20:02, but when opening the track in SoundForge, it was in fact only 2:47. When playing the track in Winamp, in stop, the "time" display read 20:02, but as soon as you hit play, over a matter of 5-10 secs it counted down to what was eventually the correct play time, and then went on from there to time properly... all the while playing the audio correctly.
New one for me.