Yeah, error -600 is a pain. You're trying to play something in Music, TV, or the old iTunes, and it just dies. Don't worry, I've seen this a hundred times. The fix is quick.
The Quick Fix: Kill the Media Services
The culprit here is almost always a stuck background process. Specifically, coremediod or the media playback daemon. It hangs, and every app that tries to use it throws -600.
Open Terminal (Finder > Applications > Utilities > Terminal) and run this:
sudo pkill -9 coremediod
sudo pkill -9 mediaremoted
Enter your admin password when asked. These commands force-kill the media daemons. macOS will restart them automatically the next time you need them. Try playing your file again. That's usually it.
If that didn't work, also kill the app itself. Quit Music or TV completely (Cmd+Q), then restart it. The daemons restart fresh when the app launches.
Why This Works
Error -600 is a generic CoreMedia error. It's Apple's framework that handles audio and video decoding. When coremediod gets stuck — maybe from a bad plugin, a corrupt media file, or just a bug after a system update — every playback request fails with -600. Killing it forces a clean restart. The new process loads correctly and the error goes away.
I've fixed this on macOS 12 Monterey, Ventura, Sonoma, and even the Sequoia beta. Same process. Apple hasn't changed this in years.
Less Common Variations
1. The Error Only Happens with One File
If the pkill fix works but the error comes back only for a specific file, that file is corrupt or has a weird codec. The daemon restarts fine, but it chokes on that file every time. You can try converting it with HandBrake or VLC. Or just delete it and re-download — that's usually faster.
2. The Error Happens in Safari or Chrome
Web video uses the same CoreMedia framework. If you get -600 in a browser, the same pkill fix applies. But also check your browser extensions — I've seen ad-blockers mess with media playback in weird ways. Disable them temporarily and test.
3. It Happens After a macOS Update
Updates sometimes leave stale caches. The pkill fix handles it, but if it keeps coming back, you might need to reset the media cache:
rm -rf ~/Library/Containers/com.apple.Music/Data/Library/Caches/com.apple.Music
rm -rf ~/Library/Containers/com.apple.TV/Data/Library/Caches/com.apple.TV
This wipes the playback caches. It's safe — these just rebuild as you use the apps.
Prevention: Don't Let It Happen Again
Most of the time, -600 is a one-off. But if you're seeing it regularly, there's usually something causing the daemon to hang.
- Keep macOS updated. Apple patches CoreMedia bugs in point releases. Don't skip them.
- Avoid running multiple heavy media apps at once. I know it's tempting, but playing a game while streaming 4K video in the background can overwhelm the media subsystem. It's not a resource issue — it's a priority thing. The daemon gets confused.
- If you use third-party codec packs (like Perian for old media), uninstall them. They're old, unmaintained, and cause exactly this kind of problem. I've seen Perian break media playback on every macOS version after 10.10.
That's it. You're back up. If the error persists after the pkill and you've tried variations, boot into Safe Mode (Shift at startup) and test there. If it works in Safe Mode, a third-party app is interfering. Good luck.