I just installed the factory integrated xm tuner into my 07 with jbl. I noticed that the tuner box had an 'extra' connection port. I looked around on the web some to see if I could findwhat it is for. No luck. Does anyone know if the factory unit has updatable firmware? Maybe there is some way to improve the available displays. One of the sites talked about being able to change the function of the steering wheel buttons by holding them down to change from preset to direct tuning. I haven't tried it yet, does anyone know if that works?