No internal speakers OS X Lion

I upgraded to Lion recently.  It screwed up a lot of things on my Macbook Pro 2010 15″ i7, so I clean installed Lion.  All has been going smoothly until today, when I came home from work and woke my laptop.  Fired up Spotify, and there was no sound.  Then I realized there were no internal speakers recognized.  Oh boy.

It’s late so I will cut to the chase.  I followed many posts in the Apple forums about permissions (always the first thing to try when something is amiss), PRAM reset, rename a plist key from false to true, etc.  You can read about that stuff here:

Nothing worked.  So I have an old Core2Duo 2007 mini, still with good ol’ Snow Leopard installed.  I grabbed the file from it, copied the contents and pasted them into the Lion’s file.  Saved the file (you must do this from a sudo TextEdit session) and it worked.  Probably deleting the file and rebooting would also work but I didn’t try that.

Here are the commands in Terminal to type (thanks to Chaindler from AD), followed by my contents of the working file:

1. Open Terminal

2. Type this “sudo /Applications/"

3. enter your password

4. In textedit open /System/Library/LaunchDaemons/

5.  Copy all of the contents with command-a, and then paste them into a new file.  Save that file as a backup.

6.  Paste the following(everything between the start and end markers, but not the markers themselves):

******Start Marker—Do not copy this line**************************
<?xml version=”1.0″ encoding=”UTF-8″?>
<!DOCTYPE plist PUBLIC “-//Apple//DTD PLIST 1.0//EN” “”>
<plist version=”1.0″>

<?xml version=”1.0″ encoding=”UTF-8″?><!DOCTYPE plist PUBLIC “-//Apple//DTD PLIST 1.0//EN” “”><plist version=”1.0″><dict> <key>EnableTransactions</key> <true/> <key>Label</key> <string></string> <key>ProgramArguments</key> <array> <string>/usr/sbin/coreaudiod</string> </array> <key>KeepAlive</key> <false/> <key>MachServices</key> <dict> <key></key> <dict> <key>ResetAtClose</key> <true/> </dict> </dict> <key>UserName</key> <string>_coreaudiod</string> <key>GroupName</key> <string>_coreaudiod</string></dict></plist>

******End Marker—Do not copy this line**************************

7. Save

8. Reboot

Good luck!