Q: Just installed lion...no sound

I suspect that the driver failed to install during the system bootup. Intersting if I connect the earphone with it before or after bootup, the problem solved

Yeah, its weird. I tried almost everything before formatting (safe mode, repair permission, clearing cache, with/without headphones etc). Except what Ashka advised:

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

Did you tried it?

There is no such

Here are the locations

This should help your search

Christopher Reynolds, ASQ CRE, PMP, BS IS

Thank you. But this is the file that missing and not sure the missing file causing all this problem

We are all looking for the FINAL solution to the issues that are being seen.

Sound is just one of my issues - I will be getting back if this was the issue for me

Christopher Reynolds, ASQ CRE, PMP, BS IS

Problem here is, audio output is working, but not input. Have an early 2008 Mac Pro. Real drag. Arggghh.

Same Apple MBP, and a related issue. Every reboot the sound is muted, hit the mute button and it comes back on. No problems from there on in. Its very consistent and I never get a greyed out icon.

But, when I first installed lion this was not an issue. Its since I have been repairing it (PRAM, SMC, Permissions etc) to get it to talk to my LED external monitor that the sound isue has arrisen.

One step forward, two back..

SBB

I have taken a look on this issue, and this is what I think :-

1. It is not a hardware issue otherwise rolling back to 10.6.8. Will no work.

2. I saw a little metal “click” on the top of the entrance hole of audio in/out jack, a short term solution is either to insert an earphone or an optical cable and uplug it afterward, which would drive to run the audio driver.

3. Hence, I believe there is a problem only with certain model of MBP, after upgrading to Lion the software fails to “click on” the audio driver of the volume control.

Before, Apple to release the new update to fix this issue, I always insert an Tousling to mini optical adapter (without cable), which helps.

http://www.amazon.com/Toslink-To-Optical-Mini-Adapter/dp/B004T67EZK

I had this issue on mid 2010 MBP. I Plugged in headphones and it started to work again. After unplugging it continues to work. I am keeping an eye out for what may set it off.

I'm having the same problem (13" MacBook Pro 2009), except that my volume is stuck on "high" (which is where I last had it.) I can't adjust it anywhere.

Last thing I did that used sound was probably watching Hulu.

And now for the final act... (Taken from MobileMe, Safari and Sound)

THE SOLUTION...

Yes folks, after working with the crack team from Apple Care (James and Company) a solution to this issue was discovered.

For all the about issues, it comes to this.

Reboot System

Hold Command+R (Recovery Mode)

In Recover Mode, select Disk Utility (This insures that Macintosh HD is not mounted)

Run

Disk Repair (x2)

Disk Permission Repair (x2)

Restart

If still having issues

Command+R

Install in Place (Reinstall - This takes and replaces any files that may have been overwritten and rewrites them)

After installation, check if system is okay, If not

SMC (Shift+Option+Command+Power)

HW Reset (Command+Option+Power)

PRAM (Option+Command+P+R)

If still not functioning... Here is the FINAL Solution

Since this formula is to take out the grossest of errors on the OS side, Take a moment to create an alternate user with Admin permissions

Log in to this account

If everything is now functioning, the corruption is a hangover from SL and you will need to move all of your data (only the data) to the new account.

Beware of MobileMe.

Before starting the transistion to this account, turn MobileMe off - No Syncing, No iDisk, No Nothing!  This will prevent MobileMe from rewriting the corrupt information into your new account.

Collect all of your data, serial numbers for 3rd party Apps, eMail and other items.  This will take some time, but it is worth the ride.

Once this is all complete, your system will be rock solid stable.

Christopher Reynolds, ASQ CRE, PMP, BS IS

Doing SMC seems fix, but once reboot, the problem remains

SAME PROBLEM...

MacBook Pro 13 (mid 2010)

The issue occurs 8 of 10 times, sometimes a shutdown and power on helps.

But at the moment, no soundcard was visible.

Any solutions???

Thanks Jo!

Repost from earlier in this thread..  It does work.

My system has been completely stable after this.

Reboot System

Hold Command+R (Recovery Mode)

In Recover Mode, select Disk Utility (This insures that Macintosh HD is not mounted)

Run

Disk Repair (x2)

Disk Permission Repair (x2)

Restart

If still having issues

Command+R

Install in Place (Reinstall - This takes and replaces any files that may have been overwritten and rewrites them)

After installation, check if system is okay, If not

SMC (Shift+Option+Command+Power)

HW Reset (Command+Option+Power)

PRAM (Option+Command+P+R)

If still not functioning... Here is the FINAL Solution

Since this formula is to take out the grossest of errors on the OS side, Take a moment to create an alternate user with Admin permissions

Log in to this account

If everything is now functioning, the corruption is a hangover from SL and you will need to move all of your data (only the data) to the new account.

Beware of MobileMe.

Before starting the transistion to this account, turn MobileMe off - No Syncing, No iDisk, No Nothing!  This will prevent MobileMe from rewriting the corrupt information into your new account.

Collect all of your data, serial numbers for 3rd party Apps, eMail and other items.  This will take some time, but it is worth the ride.

Once this is all complete, your system will be rock solid stable.

Christopher Reynolds, ASQ CRE, PMP, BS IS