802.11b and couches

I recently purchased a Cisco AIR-PCM352 (for the low low price of $137.89 at the U of A bookstore.) It works fine with my laptop on campus and at my apartment. But for some reason, will not work when I am on the couch, despite the fact that the couch is closer to the Router than the room I am in right now.

I'm thinking that the couch cushions might block the signal, but I can't see why something like a couch should be a reason for no signal. Does anybody else have this problem?

I dont know the solution, but

It will work absolutely everywhere but on the couch?

Could the metal springs have an effect on the signals?

Some of the strangest things can block signals. Set up a wireless weather thermometer a while back. Had to move the receiver. The aluminum film of a large wall mirror was blocking line of sight. Try to figure out the line of site path and see if you can figure out what's in the way. I don't know the frequency you use but I'm quessing that it is high enough that couch springs shouldn't matter, you need a conductive sheet to block signal.