My internal speakers fall silent
I have a mid-2011, 27-inch iMac, running Yosemite 10.10.3. When I restart or shut down my computer, my sound output setting changes away from using the internal speakers, which is not what I want. Is there a way to stop this happening? I don’t recall this happening in previous versions. Roy Lund
With Yosemite, the default sound output changed to use an HDMI device if one is connected. This means an external monitor’s speakers are used automatically. On an iMac, that’s probably not what you want, but OS X should remember what you’ve manually chosen. Check the permissions for /Library/ Preferences/Audio/com.apple.audio. SystemSettings.plist by right-clicking the file and choosing Get Info. The _coreaudiod service should have read and write permissions in the Sharing & Permissions section at the bottom. If it doesn’t, you can fix it by opening Terminal and typing sudo chown 202:202 /Library/Prefe rences/Audio/com.apple.audio. SystemSettings.plist to set the correct ownership and then sudo chmod -N $_ to remove any access control list that is overriding these permissions (the $_ repeats the previous command’s last parameter). Also run Repair Permissions in Disk Utility in case whatever messed up permissions for your audio setup affected other files as well.
If Yosemite forgets sound preferences, check permissions on its audio system settings file.