Adding audio file to project causes existing tracks to sound "warbly"

I have a project with several audio tracks, most of which were recorded in that project. The whole project is 48khz 32 bit. I went to add a track that is the same sample rate / bit depth on another track and as soon as I do, all the other tracks now sound warbly, for lack of better word. It is as though the whole project is now (badly) being attempted to quantize, but I can see now settings that would account for this. I’ve tried several times to reload the project, start from scratch and it’s absolutely the addition of the new file that is causing it, but I can’t for the life of me conceive of what would cause this to happen.

I’ll add that even removing the file from the project and deleting from the pool does not revert the behavior of the whole project - the audio is still glitchy. Reloading the project before the file was added in the first place causes things to play normally. There is nothing discernibly wrong with the file itself and even if there were, I don’t know why the behavior would not revert after removing it from the pool.

EDIT: Actually it turns out this project is just messed up, period. If I open it before importing this file, it plays normally at first, but each subsequent time I play it, it gets more and more warped - the stuff I’ve recorded previously just begins sounding more and more warbly. I’ve tried other project files to see if the behavior is similar and they all behave normally. I can identify no setting that would account for this. Is it possible this project just got corrupted somehow?

Hi,

Tr to Backup Project from the File menu, please.