It resets on startup. I turn off the car with shuffle by lists, and when I turn it on again it shuffles everything without selecting any song or anything.
I'm not sure how familiar you are with car radios, they usually use a launcher app from which you control other apps. I set Poweramp as default Audioplayer, and now in main menu of my radio I have play buttons. Are you suggesting using those resets the shuffle setting?
I figure it has something to do with the device not receiving any power at all when the ignition key is taken away, though I set the RNS to power down slowly.
As I said, this didn't happen during trial, or even during the time I got that nagscreen telling me to buy. (In case you're wondering, it's a legit copy, not a cracked version. 4 bucks isn't even worth the hassle)
Not a dealbreaker, still the best player for car radio around and I tested several, but annoying.
I select my songs my tipping on the one currently running usually.