problems with their ADSL wireless routers and some people have reported them on this forum, while mine strangely chugs along even with Gb's of throughput per day for the webserver.
I did however update the firmware, which you should have an .EXE file that allows you to select the router and IP address, while setting a firmware file - which is the file you downloaded and won't open. You then wait, but this MUST be done on a hardwired computer, not a wireless one. Once this process is complete you will then be asked to reboot the router. Some routers require ftp copying of the firmware.
Remember, be careful updating firmware - it can cause MAJOR problems. See the online documentation for firmware updates from the Linksys website.
Also, try a 'hard' reset, by reseting to factory settings.