What could be the problem on Des 1100 26 switches?

Question

network hardware

Good afternoon!
Tell me good people! there are old ancient des 1100 26 and so they work, then bam, the wildest lags start in the webcam, don’t enter the losses before the switches are huge, God forbid, out of a hundred 10 will reach, and all 4 start working like this at the same time and rushing flood from them, they start sending out udp requests such a feeling they are looking for something. But the most important thing is that users have all the rules and no one complains. I could leave it as it is, but the upstream machine's Stormcontrol is blocking ports)

Answer 1

Why is the incoming traffic port as WAN signed?

Answer 2

This switch (D-Link DES-1100-26) You need to throw it away and buy another, not d-link.
There was a similar one - because of the slightest whim on the supply network, it lost vlans. Replaced with HPE.