Google Maps and Mapquest nuke HTTP access for entire LAN?

I'm on a wired home LAN with a Belkin SOHO router with the latest firmware. My PC is hooked to a Netgear GS108 switch linked to the router, but the problem has also occurred with other cabling configurations, e.g. hooked up to a different switch, or hooked up directly to the router. My PC has the latest free editions of AVG antivirus, ZoneAlarm Firewall, Ad-Aware, Spybot SD, and Javacool Spyware Blaster. Zonealarm is set to Stealth mode, and has the host file locked. Spybot has the "System settings protection" of its resident program turned on.

I'm having a very odd problem. For some reason, 2 out of 3 times that I bring up directions in mapquest or google maps, it freezes halfway through loading the map, with several map sectors showing only blank grey squares, and completely nukes web access for the entire LAN. The LAN network and its WAN connection are still active, with connectivity, and other protocols still function (e.g. Thunderbird can still talk to its servers and grab my email, online PS3 games keep going without interruption). However, HTTP access is completely kaput for every machine on the LAN.

Waiting does not seem to help; the only thing that I have found to restore HTTP functionality is rebooting the router. Nothing, so far, other than map websites, has produced the same effect. This occurs in IE6, IE7, and Firefox 3.0.5

This is really odd.. any suggestions on how such a specific operation in a web browser on a single machine could reproducibly shut down web access for the entire LAN? (When I told my roommate this, he thought I was crazy, until it took me about 5 seconds to reproduce the problem and eliminate web access on his machine.)

 

Bump... any suggestions on this?

 

Bump, anyone got any thoughts? I know I'm not supposed to bump but it's been almost a month and a half.

This is killing me. I'm having to reboot the router anytime a website that has a map component loads because they all seem to be based on the Google Maps app. It's really annoying.

The odd thing is, even while HTTP access is nuked, even while the router is rebooting, other internet services keep working without interruption. I can even stay connected to an MMORPG server during all of this.

 

Could this be to do with the firewall on the router?