Try the .limewire fix. I do not think it is the RCA cable modem I am using on (RCA Digital Cable Modem) and am having no problem. If the .limewire fix doesn't work you can try resetting the modem by unplugging the modem for 30 sec then plug it back in. On the back of the modem there should be a reset button, push it in for 15 sec after you plug it back in. It will reset it to the default settings if something got messed up somehow. The Link below has the .limewire fix in it.
http://www.gnutellaforums.com/showth...threadid=36420