Can you see if Beta 6 fixes the issue?
Found out that the tweak "NoAccSplash" which disables the "Accessory Attached" splash screen that shows disabling the iPod app when you plug your iPhone into certain audio accessories. With this tweak enabled you just get a black screen on the AppRadio deck when the AppRadio.app is running. Other apps like Pandora worked fine but not the AppRadio App Home Screen.