mp3 tempo drift

[pheebink]

Hello
I am new to this forum and could not find an answer to my problem.
I am in a trio that is planning to use backing tracks from http://www.version-karaoke.com
This site suggests using Audacity to edit their files.
Some of their mp3 have solid tempos with no tempo drift and some do not.
It is necessary for me to add a "click track" for live performance but some of the mp3 files will drift away from the click tempo.
How can I "correct" the tempos of the mp3 with Audacity?
Paul

[steve]

It's a tricky job, but the tool that you need is the "Sliding Time Scale / Pitch Shift" effect (in the Effect" menu).

[pheebink]

Hello Steve
Thanks for your answer on Audacity and the tempo drifting on my mp3.
I am a drummer with good time so I thought that it would be easy for me to record a manual click track with the drifting mp3s. I played the song through my headphones and recorded my taps using a stick and plastic cup. I ran a song down and kept time with it but when i played it back my recorded "manual click track" started great but soon drifted a great deal. As I said my time is good so i am confused as to how click got so far off...any thoughts on what is happening and how to fix this?

[steve]

I think the problem may be with your sound card. If it is, then it may be possible to improve it by changing some settings, but before doing that it would be a good idea to try and establish if that is the problem or not.

Do you have a CD burning program that can make audio CDs from MP3 files?
If you do, then make an audio CD from the MP3 files that "drift" in tempo.
Then play the CD on a stand-alone CD player (not your computer).
Does the tempo still drift?