Help, "server"lag then scoreboard and another addon freezes

[Drewbie]

Hello everyone!

So I have a problem on my server, it spikes now and then and sometimes after a while the "scoreboard" and a addon called mayorvote becomes uninteractive, you can no longer scroll the scoreboard or click on who to vote for as mayor.
It's really strange and the F4 menu and everything else still works, these things just seems to freeze and if you "reconnect" it's fixed.

If someone could help me I'd really appreciate it.