One other option to plugging your iPhone, is to Air-Stream your music (ex. Pandora, Sirus XM, Music stored in iPhone). The 2011 - 2012 JBL system supports Air-Streaming. Works through Bluetooth. If i recall it was not to difficult to set-up. It works without fail.
As for the USER Options while in motion, the system is setup NOT to allow you to use the nav, dialing options, etc... it greys out those options. You can override this as i did long ago. I purchased a device from Prestigious Society, which is simply plug and play. it provides a 5 min window to dial, search out POI, type in addresses, etc, just as if you were in a stationary position. If the 5 min is not sufficient, you just activate it again to continue imputing information.
These two enhancements will bring new life to your JBL system.
Hope this helps...
PR