Why does Itunes change the length of songs?

So here's my issue and a little bit of background information:

I opened an MP3 in itunes that is 3:25 in length (Blackmill- "The Drift"), and itunes displays the song length as 25:10. the song is not 25:10. it is 3:25, and both Quicktime and Audacity agree. although i changed the stop time of the track to its original 3:25 (just so that there's no issues, you know) and I thought that Itunes would have updated the length of the song, but it still mistakenly reads the song as being 25:10 in length.

if I skip to different points in the track, the song continues to play instead of just having silence, but I don't understand what is going on, and i don't understand what causes this phenomenon.
The same issue occurred with a file a friend gave me, "Undead" by Hollywood Undead. I deleted it a long time ago, but we both had the same issue. the file was also on my older mac and even then displayed a length of over 25 minutes.

I have a 21.5" 2011 iMac running 10.7.5 (64-bit) and itunes 11.0.1. (in 32-bit mode)

My old computer was a 13" 2005 MacBook (black), running 10.6.5 (64-bit) and whatever version of itunes that was released in fall 2010... in 32-bit mode.

My friend's computer is a 2010 MacBook (white) with the same operating system/itunes as my old computer.

so, what causes Itunes to do this?