Lag spikes, anywhere?

I noticed today, that i got a big problem with lag spikes. Yesterday all was fine, but ingame i get every few minutes around 300-500 ms and a delay about 2 seconds. Than my ping goes fine again and a few minutes later the same problem. My connection is fine every other game works like it should work. I reboot my Internet, started my pc new but it's always there. Anyone with the same issue? :o