(going from memory)
One thing saving does is clear out caches

After saving the "undo's" are not available (right?), so it does clear out something...

I understand you are saving right away, so there are no 'undo's in the project, just pointing out that saving does clear out some things. Maybe the system is not loading RAM right unless the save process is done, or something weird.

I do not work here, but the benefits are still awesome
Make your sound your own!