Getting Debug Logs
If you're having a problem with Background Music that the developers can't reproduce, it can be helpful to get debug-level logs (more detailed log messages) and attach them to your issue.
Option-click on the Background Music icon to reveal the Debug Logging menu item and select it. Then continue from Getting the log messages. After you've finished with that, you'll want to disable debug logging because it uses a bit of CPU and can cause audio glitches.
You only get debug logs for Background Music.app this way. We're still working on it for BGMDriver and BGMXPCHelper (the virtual audio driver and a helper program), but in the meantime you can install a debug version if you want the complete logs.
The most recent debug version is currently 0.4.0-DEBUG-f20dd57, but you may want to check the releases page to see if there's a newer one. Or install from source.
After you've finished getting logs, you'll want to uninstall the debug version and reinstall a non-debug version. (The latest snapshot version from Releases, probably.) You don't want to use a debug version all the time because they're compiled without optimization, so you can get audio glitches when there's high CPU load.
Paste this command into Terminal.app and press enter:
log stream --info --predicate 'process == "coreaudiod" or process == "Background Music" or process == "BGMXPCHelper" or composedMessage contains[cd] "Background Music" or composedMessage contains "BGM"'
Close Background Music and reopen it and you should see the log messages printed in Terminal.app. Reproduce your bug, copy all of the log messages and attach them to your issue.
It doesn't work quite as well, but you can also use Console.app to read the logs. Search for messages from the Background Music and coreaudiod processes:
