Q: Just installed lion...no sound

Same problem here MBP 13  2010

I ran into the same problem on my MacBook Pro (Late 2009). Resetting my system's PRAM and SMC didn't help, nor did setting the sound system to 32-bit in Audio MIDI Setup. What DID fix the problem was starting my Mac in "Safe Mode," then rebooting.

Apple has instructions for invoking "Safe Mode" at:

http://support.apple.com/kb/ht1455

Thanks very much for the great tip, it works 100%

The SAFE MODE trick didnt work for me

Fix your permision files !!! and reboot

i use Iceclean

I've got the very same problem. Tried all the tricks mentioned so far but no success at all.....safe mode, permission rebuild, audio-midi setup....reboots over reboots, nada! Very frustrating.

For what it's worth a fix from Leopard:

USB Speakers not working

I deleted the com.apple.soundpref.plist from the MAIN LIBRARY -PREFERENCES - (not the users library).

Again in the same PREFERENCES folder I went into the AUDIO folder and deleted com.apple.audio.DeviceSettings.plist and com.apple.audio.SystemSettings.plist

Best

@Eridanx @Keenast @Ashka

You sure you trying the Safemode correctly? Make sure your machine is powered off and connected to the charger. Switch the machine on and press the left shift (left side above the "fn" key) when the boot sound chimes. Let the key go as soon you see the Apple. A grey bar should appear under the Apple and the OS should boot very slowly and it took me on both my machines around 2-5 minutes till everything was booted. Shut the machine down (not restarting) takes again a considerable amount of time 2-3 minutes in my case. Boot up and everything should work.

I already fix the issue i just repair file permisions using IceClean

Thnks

@wettmann:

I redid the procedure exactly as you said and for good measure also trashed the two files
Ashka was mentioning and IT WORKED !

Many thanks really - that thing made me crazy ;-)

****, I just tried booting in Safe Mode correctly. It showed the progress bar under the Apple Logo and also the spinning logo as well. I also tried deleting the Audio files like Ashka mentioned and its still not working.

Finally sound is working, but I had to reinstall whole mac (backup -> format -> install snow leopard -> update snow leopard -> install lion -> use migration assistant) and it took some time

same problem, reinstalled lion three times do not work

Reinstalling Lion (without format) didn't work for me either .

I did a couple of Permissions Repair and now the sound control is back,

Apparently it worked.