I'm have both WRT54G v2.2 and WRT54GL routers and tried Tofu 13c and Thibor 15c firmware versions and have issues with a Vizufon 4000 videophone connected to the router. Sometimes the Vizufon works correctly and other times it connects but will be missing the audio or video. The Vizufon has a static IP and is configured in the router as a DMZ device. I suspect it may have something to do with the conntrack settings and the router attempting to re-use a connection when, in fact, the Vizufon may be transmitting on a different set of ports (it utilizes very wide port ranges). If the Vizufon is connected directly to the cable modem, it consistently works without a problem. I've tried reducing the conntrack timeouts but the minimum is 600 seconds as well as reloading the firmware, clearing NVRAM, etc. Does anyone have any ideas that might help solve this issue?