I run a wireless connection from my Tivo and Empeg MLord dock via a 10 bT Hub (not switched) and a wireless bridge. It had been working fine for about a year. A few weeks ago, the empeg traffic simply refused to go through the bridged link. The Tivo was connecting properly, getting daily updates from the web. I could reach the empeg through the hub just fine. If I rebooted the bridge, it'd sometimes work but just for a while. I updated the firmware on both wireless endpoints, to no avail.
I instituted a "ping empeg -t" on a machine on the other side of the wireless link, and it's been fine since. Annoying solution, but it's working for now.
-jk