Q: Just installed lion...no sound

Success - in the Audio Midi Setup (Utilities) I changed the output to 2ch - 32bit Float and all the audio works well.

I hope, Apple fix this in an OSX update...

I finally solved the problem by changing the False to True for this plist

https://discussions.apple.com/thread/3203808?start=15&tstart=0

This may not apply to everyone, but on a Mac Pro tower on which I had lost sound on my external speakers I simply switched the cable from the port at the rear to the headphone port at the front, and the sound came back. I swear I had tried this before, but when I was using iTunes. This time I was playing a track on YouTube. Doesn't make sense, I know, but it worked. Have restarted, sound still there. And it's there on iTunes as well.

Well,

After some time, my MacBook Pro 13 Early 2011 is loading the sound drives.

I have two Users: Admin and Guest.

When I turn on my Mac, I wait for a while, something like 10 seconds before type the password.

And It seens that this time is more than necessary to my Mac load the drives...

It has been 4 days since the last time I had sound problems....

I had this issue and eventually managed to resolve it after trying ALL of the above and more!

Make sure that your /System/Library/LaunchDaemons/com.apple.audio.coreaudioid.plist file looks like this:

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">

<plist version="1.0">

<dict>

          <key>EnableTransactions</key>

          <true/>

          <key>Label</key>

          <string>com.apple.audio.coreaudiod</string>

          <key>ProgramArguments</key>

          <array>

                    <string>/usr/sbin/coreaudiod</string>

          </array>

          <key>KeepAlive</key>

          <false/>

          <key>MachServices</key>

          <dict>

                    <key>com.apple.audio.coreaudiod</key>

                    <dict>

                              <key>ResetAtClose</key>

                              <true/>

                    </dict>

          </dict>

          <key>UserName</key>

          <string>_coreaudiod</string>

          <key>GroupName</key>

          <string>_coreaudiod</string>

</dict>

</plist>

Then restore the permissions of that file by typing the following into terminal:

sudo chown root:wheel /System/Library/LaunchDaemons/com.apple.audio.coreaudioid.plist

Restart your mac....done.

Just installed 10.7.1 and all is well again with the sound! Mind you other problems still persisist so roll on 10.7.2!

SBB

Installed 10.7.1, But the issue wasn't solved! :(

Please fix this bug!

I restarted my macbook pro (mid 2010) into safe mode using the shift key at startup.

I rebooted it as soon as it started, didn't remove anything, but this was enough to fix my sound :-).

Copied from a different blog:

Answer:

To do this:

Find Audio Midi Setup in Utilities folder, on the left hand side there should be Built-In Output.

Select it and then use the gearwheel at the bottom of the panel to make sure it says "Use this device for sound output".

Hope this works for you. I am having problems getting my external speakers to work after the Lion upgrade, but this should work for internal speakers OK.

If Built-In Output does not appear in the left hand column, use the plus sign at the very bottom and see if that finds it for you. Let me know how you get on.

Hi guys,

I have a solution that works. The problem is caused by old progs that are incompatible with lion. Follow these instructions and the sound returns: http://osxdaily.com/2011/07/15/how-to-check-if-applications-are-incompatible-wit h-mac-os-x-lion/

Deep joy.

Platothefish

If you don't find a consistent solution to address your problem, give my workaround a try.

http://forums.macrumors.com/showthread.php?t=1212577

Have tried everything in this post and others including reinstall, to no avail. Guess i'll have to wait on 10.7.2 and pray for a fix. Not a problem on my 2010 Mini as it stays hooked up to external speakers but irks the **** out of me on my 15" 2011 MBP, i7 w/256 SSD. May try Genius Bar but I have my doubts. Don't believe it's a hardware issue but more likely firmware/software.

Im having the sound problem too, (it seems to do with lion and an SSD). I removed the SSD and ram, reinstalled it, and the sound works now! Even when I reboot! Werid. Im running 10.7.1, mabye this will help someone

I'm in the same situation. I have no output/input device in any audio settings. I tried:

• safe mode,
• reinstall system,
• removed some files,
• modified some audio files (e.g. part of KeepAlive),
• restarted MBA so many times
• restarted PRAM
• etc.

and nothing to helps me. I have MBA 1.1 (2008) with OS X Lion. Please help.