My Z fold 7 started to do this after an update right before the Z fold 8 was available in hand, I received my Z fold 8 and it keeps doing the same thing
This has been a problem for me as well on my Pixel 10 Pro Fold the last few weeks as well. Seems to be an app issue more than a specific phone or manufacturer issue.
Samsung Galaxy Fold users are reporting an intermittent YouTube bug that freezes video while audio continues after switching back to the app. Complaints span several premium Galaxy models and online forums, but Samsung and YouTube have yet to acknowledge the issue or offer a fix.