My mp3 in iTunes shows a time of about 20 minutes, when it really have about 5 minutes. The VLC Player and the Windows Media Player shows the correct time for the same file, what's wrong with my iTunes?
The incorrect time is most likely due to an error introduced by the encoding software. You can repair the problem by using the Convert to AAC feature in iTunes.
In iTunes 11 this feature can be found under the Create New Version → option of the File menu.