My friend Chris is creating guitar and vocal tracks in Audacity (in connecticut). He sends them to me (in Grenoble) in an mp3 file. I import this into Ableton live lite 10.0 where I use a VST called superior drummer to record midi drums using the mp3 from Audacity as a guide. I export the audio drums to a stereo Wav and send back to Chris. When he imports this into Audacity as 2 separate tracks, and lines up with the original track, the drums are 8 seconds longer and the timing starts to drift out after the first few bars. Any idea what we are we doing wrong? Digital samples in 48100 bits. Audacity version was 2.3.3. Ableton live lite version is 10.0. Thanks if you have any ideas, Calumn.
It sounds as if there may be a bug in Ableton. We have one other report of this issue: Unwanted silence added at end of exported WAV file
I’m guessing that you are referring to the sample rate. If so, then it should be either 48000 or 44100.
Have you tried aligning & mixing the MP3 & drums in Audacity on your end?
You might try some experiments to narrow-down the problem - Make a file of known length (maybe 5 minutes) with a short beep or a snare hit at the start and end. Check the time shown in Audacity and Ableton and check with a clock or stopwatch. Send the file to Chris and have him check with a clock or stopwatch.
Sometimes this kind of thing can happen when you record and play back on different hardware. The clocks never perfectly match but usually the problem shows-up when playing-back on a “cheap soundcard” after recording on a good-quality interface or good-quality USB mic. Or, it can happen if you record on one cheap soundcard and play back on a different cheap soundcard.
But… I’m not sure if that’s the problem here because if the digital files line-up on your end, they will play back at the same speed when mixed even if the speed is wrong.
I think I found the bug. In Audacity Chris was using 32 bits for his audio and I was using 24 bits in Ableton, We both installed the latest version of Audacity with 32 bits audio. I redid the drums in Ableton, imported into Audacity, imported also the original track from Chris recorded in Audacity, and hey presto - everything was aligned 
. This is probably a beginners mistake but thanks for your suggestions. Its great to not be alone when facing these types of problems. Cheers Calumn.