After upgrading OS X yosemite, Mac users reported lot of issues.
- Mac users get popping noise when playing audio or video,
- No sound in Safari and other browsers when playing videos
- Can’t adjust volume for speakers.
Launch Terminal and type the following command.
sudo killall coreaudiod
Fix 2: Change the output source
OS X Yosemite upgrade process change the sound output source from default to installed HDMI display speakers.but Mac does not have any control to this speakers. So this issue might happened. If you attached any external speakers source, Mac wants to make that output device.
Navigate to System Preferences -> Sound and change the output device to Internal speakers
Fix 3: Change Os X Yosemite System Preferences
Navigate to System Preferences -> Sound. Then select the “Play Feedback when volume is changed” check box.
Fix 4:- Change the system preferences again
Navigate to System Preferences-> sound and make the tick on “Show volume in menu bar”.
Fix 5:- Change the audio port settings
If you are already using HDMI external display with sound, navigate to System Preferences ->sound and change from HDMI to Headphone port. Because some Mac users thought HDMI sound devices no longer controllable on OS X.
Fix 6:- Reset Pram
- Shout down your Mac
- First find Option key, Command (⌘), P, and R keys in your keyboard.
- Then turn on your computer.
- Now hold Option+Command+P+R keys combination before the gray screen appears. Continue to holding these keys down until Mac restarts and the startup sound for the second time, then release those keys.
Restart your Apple Machine
Restart your computer (iMac, MacBook Air or Macbook Pro).