I have only been doing this a few times but noticed similar problems trying to do the mix myself. I also noticed that the individual track recordings may seem time stretched in comparison - so that I may have to shrink or stretch them to line up. It's almost as if there is some clocking drift - likely or possibly due to jitter which we do see some of on the indicators. I need to do something more exact to test this - creates some specific test files to play into JK to see what's up with the drift and offsets.
"They are placed in C:\Users\*yourname*\Music\JamKazam\Recordings (for Windows)."
...and while this may be true, it is a terribly inconvenient way to work with the audio with GUID-stayle file names. Much easier to select export in the File Manager dialogue and have the tracks appear with "human" names in Documents\JamKazam\Recordings. You end up with two copies of the audio on the computer, which is a bit of a bummer, but I reckon you can erase the GUID versions after the "Export" and all will be fine I think.
"They are placed in C:\Users\*yourname*\Music\JamKazam\Recordings (for Windows)."
...and while this may be true, it is a terribly inconvenient way to work with the audio with GUID-stayle file names. Much easier to select export in the File Manager dialogue and have the tracks appear with "human" names in Documents\JamKazam\Recordings. You end up with two copies of the audio on the computer, which is a bit of a bummer, but I reckon you can erase the GUID versions after the "Export" and all will be fine I think.