funny your write this, I have the pioneer remote control (I love it!) but its is still very fussy with my homemade IRMan and the IR sensor I am using. I think the issue is the IR sensor works on 36-38KHz and from what I have read alot of Pioneer equipment is on 40Khz.
I have found a local supplier of that sells about 6 different flavors/freqs of IR sensors, I am gonna get around to buying a few different ones and see if I can get a better working signal.
On that note, does anyone know the IR freq of the Pioneer steering wheel remotes? or how I could find out for sure?