it seems like something wrong with the [SteamNetSockets]
I just found these error code when I was suffering the fps drop problem.
I got good enough hardware configuration for playing any new 3a games. So I don't think it's just some normal low performance issue.
Actually it occurs to both me and one of my friends when we have party games. He also experienced the same situation as me. And any one of us reconnect the game, the problem would be solved immediately.
I got some reply from valve customer service. They also have no idea about this. They just suggested me to lower my video settings which I believe is not playing the role in this case.
It could be some local settings problem I guess, or internet services issue that I cannot sure.
The operation system on my pc is Windows 10 1909. My internet provider is Chinanet.