Sound level at 100% after restart

Question

The output sound level on my Mac after restart is at 100%. It is extremely annoying because I use headphones a lot and a pair of amplified speakers (when not using my headphones). Just some minutes ago it almost destroyed my ears. I heat it!
Does anybody out there can please help me to solve this problem?
Thanks in advance.

Answer 1

Zap the coreaudio process in Activity monitor, like this:
1. Open Activity Monitor.app (Applications > Utilities > Activity Monitor.app)
2. Select ‘All Processes’ from the drop down menu next to the search bar (called ‘Filter:’) and type in ‘coreaudio’.
3. Select the process name and click the ‘Quit Process’ button at the top. Chose ‘Quit’ or ‘Force Quit’ from the resulting dialogue box.
The coreaudio process will automatically restart itself (if you look closely at the PID number in Activity Monitor you’ll notice it changes after you hit ‘Quit’) and your sound problems should be solved.
If that doesn't work, return soundprefs to default like this:
4. Open Terminal.app (Applications/Utilities/Terminal.app) and copy/paste this command into the Terminal window
rm /Library/Preferences/com.apple.soundpref.plist
then press ‘return’ on your keyboard.
5. Restart your mac and test.