Multiple Bugs since IOS 14 Upgrade

Hi,

last thursday i updated to IOS 14.4.2. Since then, the iphone x started doing weird things.

Vibration doesn't work sometimes.

The iPhone crashes often (especially while watching videos or any other media type) and sometimes restarts from itself.

The Phone does not play ANY sound out of the speakers.

On calls, throu the upper speaker sometimes you hear a loud rustle and the called person, sometimes you hear absolutely nothing. Changing to speaker ends the call.

Youtube videos can't even be played. The video loads the first picture, but does not start.

To sum things up, everything (music, installed apps, phone calls) that plays sounds or videos does not work since the upgrade.

I also read some of the analytic logs on the phone. There are a lot of log files about kernel-panic and other logs about crashes of the mediaserverd.

I tried everything (factory reset, installing new ios version manually, ..) nothing worked.

I'm desperate. Has anyone an idea what to do?

Thank you.