weak airport express signal

Hi, ive had my macbook pro connected to my airport express for about 5 months now. For the first couple months I was getting full strength all of the time. However in the past couple months its been consistently at 4/5 bars. It doesnt seem like a big difference but I get around 18 mb/s at 5 bars and around 3 or 4 at 4 bars which is huge. Im getting this weak signal as I speak even after i've moved my airport to within a foot of my laptop. The problems seemed to have started after apple released those updates a while back (I cant remember what exactly for but I remember it had something to do with airport). Is there any preference I can change (interface robustness doesnt help) or anything at all I could do to figure this out? thanks.

no one knows? and yes I did do a search...is there a different channel setting or something or a way to reset everything? any ideas would be helpful.