Hello, Great site with lots of info. I've been looking here while I was picking up my new truck that luckely had the AVIC-Z2 already installed.
So today I was just messing around and was trying to play a DVD for the kiddos while driving. Now I know my brother had a toggle switch in his vehical for some other brand player, so while at a stop I put the ebrake on at 1 click. Viola, the DVD was showing video now, I drove about 1/4 mile like this at 25-30 mph and then disengaged the ebrake because of the ding-ding racket it was making.
To my question, I though that exceeding the 10mpg speed would dissable the dvd playback. Why did it not? Does this mean that all I need is the e-brake thingy?
Also, when I got the truck the unit was freezing and locking up, I applied the latest firmware patch and now my unit is the 2000500 or something and n o more issues are beiing seen. 
Thanks and sorry for the winded note.