Tracks get out of sync when overdubbing


I’m using Audacity 2.0.5 on a 2008 Mac running OS X 10.6.8.

I am a music teacher trying to record rounds and vocal harmonies for my students using the built in mic on my MacBook, and headphones.

Since downloading Audacity 2.0.5, when I am attempting to recording multiple tracks and I overdub a second track, the two tracks are significantly out of sync.

I used the Latency Test with the click track suggested online, and that fixes the issue when I’m only overdubbing once on top of my original – I’ve found that I need to set my latency around -389 milliseconds.

But when I overdub a third time to add another track, the timing is significantly off from the first two. If I continue to overdub more click tracks, the 4th and 5th tracks are in sync with the 3rd track, but they are all out of sync with the first two tracks.

I tried quitting all of my other applications and turning off Airport, but the same issue occurs.

This was never an issue when I was using Audacity 1.2, and I tried downloading 2.0.3, but the same issue is coming up as with 2.0.5.
clicktest2.aup (1.8 KB)
clicktest.aup (3.21 KB)

AUPs aren’t sound files. They’re text files to manage Audacity Projects.

However we may not need you to upload samples. We believe you.

Note the timing difference between two and three.

Do the test again from a clean start (leave your new correction applied) and is the timing still the same distance off and still between two and three?

Exactly how are you doing the latency test? Jam your headphones against the MacBook microphone? Did you have any trouble finding the microphone?