First 2-3 seconds of Maps directions cut off on Bluetooth CarPlay: SOLUTION HERE
First of all, it's really annoying that this forum locks questions before a solution is found. When I tried to resolve this problem, I found at least four matching questions and no helpful answers:
Navigation Prompts Cutting Off - Apple Community
Map tools cut off for first couple of sec… - Apple Community
maps prompts cut of first 2 -3 seconds - Apple Community
Ios 14 bluetooth cuts first 2-3 seconds o… - Apple Community
...and now that I've figured out the solution, I can't reply to any of those threads to share it because they are all locked and are not taking further replies. Apple, please fix this — it makes it really hard to find actual solutions.
Any rate, here is the actual solution: go to Settings->Maps->Spoken Directions and turn off "Directions on Radio."
This setting does not work well with some car bluetooth systems, causing them to treat navigation prompts as phone calls with poor results (cutting off the first few seconds of navigation prompts, sometimes causing music/podcasts to erroneously start playing after a navigation prompt, etc.)
This does mean that if you turn on the am/fm radio in the car you won't be able to also hear navigation directions over the car speakers. But better to hear the complete prompt through your iPhone speakers than to hear an incomplete prompt through your car speakers.