Audio is not in sync with music when using Audacity?

I have two mp3s that I am trying to put together. The beats go together in the beginning, but as the 2 mp3s progress, they get out of sync.


If the music you are mixing was played by live performers, then as they play the tempo speeds up and slows down. Two songs that are done with drum machines would both have perfect timing, and if the bpm was the same they would match right up. Songs played live are not perfect, so if one song is slowing down and the other is speeding up, your tracks will get out of sync very fast. Since the problem is not a constant, but a varying change of tempo, speeding up or slowing down a track will not help, it will just sync a different section of the song. Trying to do this with each section of the song that gets out of sync will not have good results. You cannot fix it with Audacity.


First, examine the files. Do they really sync up or are they close enough in sync that it takes a while for the difference to become apparent? For instance, if one of the tracks is even 1/60 of a second off, after a minute they will be a whole second out of sync.

As to correcting the problem, gentle use of time stretching and alignment in the mixer might fix the problem. Otherwise, you can break the files up into smaller chunks, giving you better control over positioning specific beats to make them in sync. Trim and insert silence can also help.