Audio Tracks Lagging Behind

I am putting a song together in renoise that involves recorded parts from live musicians. The tracks that one musicians sent me do not line up with the rest of the parts in the file.

I tried playing the tracks together with an mp3 I made from the original renoise file of the song, and in that one, everything lined up perfectly. The line up perfectly on the musician’s studio computer as well.

What might cause the tracks to slow down as they are being played? I checked the CPU usage, and it was a 4%, so it’s definitely not overload. I’ve had files work just fine and use way more of the CPU…

Make sure the sample rate you’re using is the same sample rate they were recorded at.

PDC?

If the lag has consequent delay then setting the track delay values might solve it, but it sounds like the tracks start in sync and phase out of sync slowly…
That is a different problem that cannot be solved with the trackdelays.

maybe if he has pdc turned off as default, and a plugin that causes delay is switched on mid-song?

What’s PDC?

Plugin Delay Compensation.
Some plugins lag behind the main audio stream because they have a delay. These plugins usually tell the host how much msecs or samples delay they are behind. If you turn on PDC, Renoise will delay all other tracks that amount of msecs or samples in order to synchronize the song.
But considering the fact that you can get your song in line with the audiotracks outside Renoise, i don’t think that PDC is the problem, i just think that the audio-tracks need to be advanced and the rest of the tracks delayed. I currently don’t know how how the audio-track is being synchronized (through ReWire or directly loaded into Renoise?)

I loaded it directly into renoise.

Might be the best if you upload a small example XRNS, so that we can see and test the problem in action?

maybe far fetched, but the bpm input box also accepts fractional input. You may have (accidentally) entered fractional values? This can be checked if there is a dot in the bpm input box.

This would also recreate the problem with the rendered song outside Renoise.
But it was mentioned that the rendered song did not posed problems when mixed outside Renoise.

If this is on a laptop i would check if there were no CPU saving power management options were turned on (Like Intel Speedstep or Dell’s smartpower or something called like that)