Our BT HomeHub is located downstairs whilst my PC and Xbox 360 are placed upstairs. Despite the HomeHub and my PC being at opposite sides of the house, my PC stills receives a good wireless internet connection. My xbox 360 is connected to my PC with an ethernet cable. I can connect to xbox live but I can only get a "strict" NAT type.
I enabled UPnP in my BT homehub configuration page 2 years ago and its still enabled, so I can rule that out. I've also tried restarting my router, many, many times and it still stays strict. I've tried forwarding instructed ports on the "Application Sharing" page on the BT Homehub, although as I'm a novice I wasn't sure to forward the ports to my PC (as that has the internet connection) or forward the ports to the Xbox 360 device, so I did both using seperate profiles. That didn't work neither.