Forbidden Donut

I have been getting ping spikes lately on only certain servers on counter-strike(just so happens to be only my clan's servers). My ping will be fine anywhere from 5-35 than all the sudden it would jump up to 300-500, now I will either be kicked for having high ping, or my ping will go back down. Here is the thing, my roommate's ping does not do this on any servers (even when he plays the same server with me)his is always lower than mine (for example: mine was at 20 his was at 8). This doesn't happen to me on any other server, or any other game. I cleaned up my registry with a registry cleaner, I used CCleaner, I disk defragged my comp with Auslogics, I ran a virus check with AVG, and I have no firewalls running. And, this problem is still happening on only my clan's servers on CS. This happened to me last semester also, but I wasn't in the clan yet and even though their servers are my favorite servers I just played on other servers and remarkably after winter break it stopped happening.

All of this doesn't add up to me, and I am completely lost of what to do. Does anyone have any suggestions?