I recently deleted all my iTunes music since I listen to everything on Spotify or my podcast app (Downcast) now. I also updated to the iOS 11 public beta. Around the same time my car stopped playing anything via the USB cable, the car just said "no song" so I assumed it was an issue with the beta.

Literally yesterday I read about this "fix", so i re-downloaded the Music app and put just one song on it... yep it works!

Car players apparently assume you will only ever play music from the "default" library/app so when you connect it and it sees an empty library index, it assumes nothing can ever be played and just stops you there.

Very dumb.

First year BMW i3 recognizes Spotify and others just fine on current relase iOS and earlier as well, I think.

I'd conjecture it's a matter of how thoroughly apps got debugged by the vendors.

Reading the “(don’t ask)” line was probably the funniest thing I’ve read in a while. I instantly got an image of a person quietly embracing defeat after endlessly trying to convince their partner that there was a better way of doing a task.

Another workaround instaed of having the music app or adding a single song as many people have mentioned is opening whatever app you perfer to play music and hitting the play button prior to plugging it into your car system. Then, as the iPhone is plugged in and your car recognizes it, it will see an audio file on the car - the one that is currently playing. It will continue to play that song.

While my car is in the shop getting unsmashed I've had the pleasure of four different cars and four different sound systems in as many weeks. That's how I know the workaround won't get it done on a Peugeot 308. "Spotify's playing? Nah, let's hear that song you like whose name starts with '('. Spotify's grabbed the audio output again, almost as if you opened it again and pressed play? I can help... And you wanted it on single-track repeat, right?"

Never thought I'd be happy to see Carplay again with its 3-ring circus of UI tomfoolery, but there it is.

I assume by "aux" you mean USB? I don't see how third party app audio wouldn't be routed to the headphone jack because the music app doesn't have content.

Yea, usb is under "aux" in my car at least, and you are correct.

Youtube has a much better library of music than Google Play Music even.

For example, my Google Home can play the Beatles on Youtube, but it fails with Google Play.

Two things. Im surprised no one at the apple store caught this. Surely they tried to use said phone to stream to a bluetooth speaker or something to verify audio was working and would notice it had NO songs to play?

Second, I wonder how much PEBKAC issues like this cost apple per year in replacement devices?

This isn’t a PEBKAC issue the way I’m reading it. Sounds like the ~~phone~~ (EDIT: the car) wouldn’t play audio from any source if the phone had an empty iTunes library.

Less rare than you might think. One of the Left for Dead games on the XBox (forget which and which) wouldn't display any LAN network connectivity unless a memory card was present.

No memory card inserted? No UI difference between "No Ethernet plugged into XBox" and "XBox connected correctly to LAN".

Insert memory card? Network magically appears.

(I may have almost taken a sledgehammer to the hardware after I stumbling across this issue while setting up a PAX game room. And no, the memory card is not used for LAN play.)

Yeah, that's how I read it as well. The likely explanation in my mind is that the process of making sure the phone is synced properly includes playing the first iTunes song, but since that fails as there is no song, the whole "sync for audio playback" is registering as failing.