Sometime, I close lid, and open again, The sound not available.

When I restart my mac, The sound back.

Is this a bug?

2 Answers 2


Yes, the same bug I have from time to time, too. I could fix it without a reboot by reloading the kernel extension for audio with these commands:

sudo kextunload /System/Library/Extensions/AppleHDA.kext
sudo kextload /System/Library/Extensions/AppleHDA.kext

I encountered the same problem. The following approach solves my problem.

open Activity Monitor, type coreaudiod in the search box at the top-right, and click the Force Quit button to manually kill the process.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .