tl;dr: disconnect from your VPN (or allow LAN connections)

I recently got an iPhone 17 and was being driven mad because, at first, CarPlay worked flawlessly on my 2019 Honda Fit (EX). However, next time I plugged in CarPlay refused to open. The phone was charging, the icon on the infotainment showed CarPlay, but it would hang for ~10s and close with a "no devices found, check cable, etc.". Android Auto worked for years without hiccups.

Nothing changed after a factory reset, reboot, etc. of the infotainment as many recommended.

I saw an offhand comment with how a VPN can cause problems. I'm connected to one 24/7 and I'm sure it worked earlier when I didn't set it up yet. I disconnected from the VPN and CarPlay immediately worked. The VPN I use has a "Allow LAN connections" setting which made disconnecting from the VPN unnecessary.

Wanted to throw this out there for people troubleshooting in the future. Not sure if this is specific to Honda or Apple, but my money is on how Apple devices do networking.

I’m about to take a road trip and I want to be able to easily play my music and it would be a huge pain to do this with iTunes. I’ve got VLC but the UI leaves much to be desired. I can’t even view my music by album in CarPlay, which is how I’m going to be accessing my music. There are tons of music playing apps out there but they are all varying degrees of sketchy. Does anyone have any recommendations?