when I try to play online FPS such as Tribes Ascend or even UT2004 demo, the wireless will stop all outgoing and ingoing internet traffic after about 20/30 minutes. This is the case for every computer on the network. Everyone can still connect to the linksys but it doesn't send data to or from the internet. The only solution is to reboot the router.
Interestingly, it doesn't have this issue with multiplayer Starcraft.
The model is a Linksys WRT54G version 7.
How do I fix this issue?