I have that same router. as do a few friends. Funny that we were discussing this router just the other day.
those god damn things are notorious for that
i've owned 5 of them in my lifetime. 3 have died.
the one i gave my mom runs like a champ for years. its an older 802.11b series.
on the other hand, i went through 3 802.11 g's before switching to a trendnet. the trendnet seems to be much more stable. i flashed the 4th linksys with linux and turned it into a wireless bridge and its been working fine too.
best advice i can give you is that they are very finicky syncing with cable modems. reset the linksys router. power everything down and wait about 5 minutes. power up the cable modem. plug in the ethernet and then power up the router. set the router to dhcp and pray.
if that doesn't work bring it over and we can all dress up in braveheart face paint and smash it to tiny pieces.
+1 - got mine way back in college, flashed to linux (surprise, surprise) and still runs like a champ.
yeah man ... thats the one i have .. **** hardly ever gives me problems.