Okay, after updating my iOS, I still have the problem where the first half a second of the guidance voice prompts are cut off. For example, instead of hearing "Turn left at the next...", I will only hear "n left at the next...". I checked the CarPlay2Air firmware, and it's the latest version (go to 192.168.50.2 on your phone while connected to the CarPlay2Air).
When I plug the phone into the USB port on the CarPlay2Air, there's no improvement. However, when I remove the CarPlay2Air and plug my phone directly into the car's USB port, everything works perfectly.
I'm kind of bummed at this point since the CarPlay2Air wasn't a cheap purchase.