How to solve the problem of incoming video quality during video calls on Samsung tablet?

Question

Video broadcast

There is a tablet Samsung Galaxy Tab A 10.5 LTE 2018 (sm-t595). A good device, but for several months now we have been facing the problem of blurry and slightly pixelated incoming video during video calls, both through public services like skype, trueconf, and our own home nextcloud and jitsi meet. The video from the tablet camera on the other end is great, and the incoming video with the above artifacts.

At first they thought that the problem was network congestion due to quarantine, but by experience they found out that the problem was in the tablet - both in the home network and in LTE, while the Samsung A5 phone, like the laptop, shows incoming video of good quality.
There seems to be no complaints about the video from the Internet in chrome and youtube.
Android 9 costs. Reboot doesn't help.

I would be very grateful for sensible advice.