Why is bluetooth audio superior to line in (from iPhone)?
I have the upgraded Command audio package on my GLC250d with Burmeister speakers etc.
What I don't understand is why the sound quality through Bluetooth audio in the car is so superior to the line in from my iPhone XS to the car's USB port. I would have thought it would be the other way around. This did not change when I retroactively installed Apple CarPlay. Any thoughts?