Intermittent Wi-Fi - Macbook/BT HomeHub2

Hello everyone. I have a macbook that can connect wirelessly to other networks, but not to the one at my folks' place. My dad and my bro (both PC users) can connect fine.

The security in the router is set to WPA/WPA2 (as is the Airport security, natch). When I view the Network Diagnostics/Airport window, I can have anything from green lights all the way down to a green only again "Airport".

Usually what will happen when the connection drops though is that ISP, Internet and Server will go red and Network Settings will go Yellow. I can sit there and not touch anything and a minute later it will all go green again, whereupon I have great signal, great speed.

I can be in the same room as the router and it makes no difference.

Any ideas? Help much appreciated!

OK, I'll just mention some things I've tried acting on advice from elsewhere:

I deleted all reference to the router in Keychain Access
I specified two DNS servers in TCP/IP settings - I tried BT's, and also a pair of google servers
I tried it with Interference Robustness on and off

I am getting an IP address but no services (web pages, email etc).

Any ideas out there? Thanks for reading

Try using a LAN cable from the bt home hub to see if your Mac can connect that way.