Oops, that sounds super weird and annoying for you.
Do you have a paid license and an updated computer?
I understand you’ve checked everything, so the only thing I can think of is to do a clean installation, not so fun but the only thing I can come up with.
Check all the drivers, but you probably already did that too. I’ve had Vegas since version 6 and using 22 now and I have never heard of anything like this, very strange.
Avoid using “cleaners” they often mess up everything. I use Revo Uninstaller to be sure there are no leftovers in the system, included uninstaller often does a poor job.
Sorry I can’t help you, but I wish you good luck, so everything works nice again.👍