CarPlay only playing out of left speaker

I HAD the problem “CarPlay only playing out of left speaker“ and solved it. As I’ve run into it twice (one rental and one friend’s car), I think it’s worth getting right.

The problem is that when you setup CarPlay on some cars (Honda, Mitsubishi, Chevrolet), music audio only come out of the front left (driver column) speaker. Interestingly, audio from other apps (e.g., driving instructions) comes out all the speakers properly.

The solution, at least for the 2018 Mitsubishi, is to pair the BlueTooth on the phone. It’s hard to guess why this might be necessary. I would have thought the lightening cable would do just fine for Audio. Still, perhaps it’s useful to pair BlueTooth just the same (so you can listen to music without plugging in CarPlay).

I don’t know that there’s a resolution. It would be nice if Apple could document it in the CarPlay setup instructions.