New connection set up last week - have called tech support, signal fine, sending out tech guy tomorrow - however i cant make sense of this

using Vista, 2wire connection 6mb ATT conn, wireless, i can browse website, stream video from my PC wirelessly to my xbox, watch Hulu in high res, connection seems fine

I load up World of Warcraft, i select Enter World and without fail my 2wire modem 'DSL' light goes red, my internet light goes out, im no longer connected, then after 10 or 15 seconds it works again, but game has kicked me

Noticed the same thing on opening or closing Utorrent as well

No other phones/devices plugged into the phone jacks in the apartment - why would joining a game cause my DSL to drop? i can only guess it throws a bunch of information to the server when i hit 'enter world' and that causes an issue that shuts my connection down

or my router hates me - all help appreciated