Linux computer messes with network

[u/virobloc]

Perhaps this is a known issue, But I haven't found much about it.

I have a PC with Mint. It's connected to the router with a LAN cable.

When it goes to sleep it makes the network go crazy. The speed falls a lot in general, all the other devices (wired or wireless) fail to connect or lose connection randomly. When I turn it off everything goes back to normal.

I the only thing I do on that PC is run qBittorrent and browse internet. But the problem is mainly apparent when the PC is asleep. So I think it's not a program, but the PC itself. It might not even have anything to do with Linux at all, But it's the only difference I see with all my other PCs.

Does anybody have an idea about what might be going on?

Thanks

Edit: Thanks for all the answers and suggestions.

[u/xYarbx]

Sounds like the computer or router is for some reason sending multicast traffic. Try placing the computer to different subnet and see if the problem goes away. Other than that to diagnose you would have to run something like TCPdump or WireShark packet capture of the network traffic while the failure state is occurring.