Ever get started working on a sequence, only to go back later and see that the lights are matching up to the music?

See this PDF from LOR. You will need to run your audio file through Audacity. This will create a Constant Bit Rate MP3 file.

[The following is from a post on the forum.]
Your problem is that your MP3 is variable bit rate..  When you ask WMP to start a song 45.5 seconds into a song, it just takes the bit rate (or average bit rate for a variable bit rate file) and multiplies the bit rate by the requested time, and starts playing from there.   But when a file is variable bit rate, you may have cases where more bit rate is used late in the file than early, and this introduces these errors.  For most uses, it is accurate enough for windows media player.  When it counts like it does with LOR, you need absolute positioning accuracy.    If you use a constant bit rate file,  your timing marks will line up…  You can use audacity to re record the file as fixed bit rate MP3.