Losing internet access when copying files over wireless LAN

[JohanG]

I cannot for the life of me figure this one out. First, let me explain my setup...

I access the internet through a WISP (hopefully not for much longer), thus a radio on my roof connected to a router in the study.
I have two Linksys wireless routers (upgraded firmware with dd-wrt).

Router 1
Configured as AP and connected to the internet.
Main PC connected via ethernet to AP

Router 2
Configured as CB (Client Bridge) located in lounge
DVD recorder connected to CB via ethernet (the DVD recorder is a networkable HDD recorder that can play DivX etc.)

The Problem
When I transfer data between my PC and the player (either way), I'm unable to browse the internet All I get is page cannot be displayed.
The data transfer maxes out @ around 10Mbit/s (limit of the player)
I normaly just leave the CB off until I need to transfer files, but it would be nice to at least access the internet while it's transferring.
I haven't been able to test data transfer to my other PC, as the wireless card in that PC is bust, so I can't determine whether it's the communication between the two routers or just the wireless LAN in general that causes the problem.

Does anybody have an idea of what the problem could be?
Is it possible that the routers interfere with the radio on my roof?

 

[Gambit]

what channel is the radio on your roof using and what channel is your wireless network using?

 

[JohanG]

I don't remember off hand what they are (can check when I get home), but they are different.
I do remember that I've up'ed the transmit power of the bridge router a little bit for a better connection (walls etc.)

 

[Gambit]

the channels used should be separated by at least 3 channel as they apparently do overlap.

 

[JohanG]

Thx Gambit, will check tonight