Trying to bring back a issue I had awhile ago. My setup is quite simple I have a Alfa AWUS036H and a 24 dbi grid antenna. I use this setup to connect to my office which is roughly half a mile away (800 meters) in a very country open field area.

A few months ago I stopped using it but tried hooking it up today in the same setup I had before (same position of antenna with angle). To my amazement airodump-ng can hardly pick up the AP at my office, a few beacons received and fades in and out. Where before I was able to get great connection and a few mbps download/upload. Also I have tried with older versions of Backtrack (version 3/4/R1) thinking it was driver and no luck.

So my question is what could have changed, did the card loose its sensitivity?