Wireless bridge troubleshooting

I'm needing some help on a test project I'm working on.  I have setup 2 wireless bridges to accomodate a network link between a clients office and home.  This client has an office located approximately 500 ft. from a 120 ft. tower.  The clients house is 2 miles from the office location.  I have configured 4 D-Link DWL-900AP+ access points in bridge mode.  Bridge 1 is between the office and tower location.  Bridge 2 is between the tower and home location.  Bridge 1 access points are configured using channel 1 and IP addresses of 192.168.1.53 & 192.168.1.54, Bridge 2 access points are configured using channel 6 and IP addresses of 192.168.1.51 & 192.168.1.52.  I have enable WPA-psk security on all using a passphrase.  I have also disable SSID broadcasting on all points.  At the clients office, there is a Linksys router with 8-port switch configured as a gateway for clients high-speed internet service.  It's IP address is 192.168.1.1.  For the long distance bridge I installed a 24 Dbi parabolic ant. at each end, and for the short bridge I installed a 8 dbi panel antenna at each end.  I'm bridging from the office to the tower, and then from the tower to the house.  At the top of the tower I have the LAN ports on the 2 access points connected with a short patch cable.  In the office I have the access point connected to one of the ports one the Linksys router.  At the house, I have a single desktop computer connected to the LAN port of the access point.  All access points are set to a rate of 1-2 Mbps, which is the lowest setting.  Let me add, I have a good clear line of sight between the 2 long range points as well.  I have the 24 dbi ant. installed on a mast approximately 30 ft. high at the house.  There are a few trees between the 2 locations, but upon a visual inspection it should be clearing the tree tops by over 50 ft. easily.

Here's my problem:  Everything seems to be working fine from a pinging standpoint, and the home pc is also successfully retrieving its IP address, gateway address, and DNS server addresses from the DHCP service on the Linksys router at the office.  I can ping all IP addresses above successfully, but when I try to access the internet from the house location through the office Linksys router it starts loading the page, but then it stops and eventually times out every time.  I can even successfully ping www.yahoo.com using the -t option consistently for over 5 minutes.  Every once in a while it will throw a request timed out, but 99% of the time it replies successfully.  I have modified the performance settings of all the access points without success.  I'm starting to wonder if something needs to be changed with my TCP/IP settings (Receive window/MTU) or something.  Or do I need some additional hardware installed to make it work correctly.