For a while now I get kicked from servers due to high ping. I thought my ping was always bad, but it's not.

I play normally for a few minutes without any high ping. I am sure many of you know that little sound that alerts you when a new player joins. Well, just before that sound my game freezes for 1-2 seconds(as if the whole system froze, but it's not) and then my ping jumps from say 90 to 400 or 500 till the match is over and I see the player stats at the end.

I think something is scanning C2 or the traffic or both. I only have Malwarebytes as my anti-virus, and I don't even run it full-time, i.e it's not on.
I did a scan for viruses last night with Hitman Pro and MalwareBytes, but nothing was found.

Ideas what is doing this?