Couple things that could be happening here:
1) They may have capped download speeds at your CO. If your friends are on a different CO, they may not be capped, or may be capped at a higher speed.
2) You may be too close to the CO. It's possible for the signal from the CO to basically drown the line, & result in slower speeds than if you were further away. When you do talk to tech support, ask them if you can reduce the transmit power setting on your modem. That may help you out.
3) You could simply be further from the CO than your friends are. Linear distance doesn't mean jack in DSL, it's all about wire length. If your neighborhood was built after your friends', & they're earlier on the line than you are, they could get better rates. The phone company should be able to tell you what your wire length is to the CO, & what your friends' are as well.
Good luck...
Viper GTS