Old topic, but i just wanted to drop in and say that I'm facing the same issue!
I'm facing this on 2 separate computers using Flirc + XBMC (frodo).
One system uses a Sony DVD remote, the other uses a Logitech Harmony (perhaps with a sony profile, don't remember).
Strangely though, i was scrolling down a list with my keyboard down-arrow yesterday and the left menu popped up (I'm fairly sure i didn't touch the left key)! Maybe its an XBMC issue?
cya
R