Aha, torrents
Some of the Linksys firmware didn't do very well with torrents, even though the router is very capable. Torrents open a large number of connections and these can overload the router's memory. If you have current firmware |(if not upgrade), look at limiting your torrent connection numbers. If that doesn't solve it I'd suggest third party firmware such as DD-WRT, combined with a
for the appropriate settings for connections and retention times of the open connections.