Q: Robotic Static Sounds USB Headset

I was experiencing random static and noise from my usb mic (as well as the built-in internal mic when I would switch to it while trying to nail down what the cause was.) SL 10.6.2, iMac 3.06 C2D. It does seem to be a "running out of RAM related problem"; a restart and leaving everything else off *delays* the problem coming back up.

I tried some of the other solutions out there on the net - creating a "midi augmented" device, etc.

This solution of replacing the AppleUSBAudio.kext is the only thing that worked. Awesome! Thanks!

Note: when you install a .kext, you have to run some chown's on it:
chown root:wheel AppleUSBAudio.kext
chown root:wheel AppleUSBAudio.kext/*
chown root:wheel AppleUSBAudio.kext//
chown root:wheel AppleUSBAudio.kext//*/
chown root:wheel AppleUSBAudio.kext//*/*/
to "clean out" the ownership requirements for kext's. Also you need to
do a chmod:
chmod 755 AppleUSBAudio.kext
All of these things need to occur from being in your terminal as "root" or "super-user": su.

Hope this helps someone else. And, of course, I hope our dear friends at Apple can track this problem down and fix it.

The excellent instructions posted by cburgess (near-bottom of previous page) worked perfectly for me - thank you!

Just upgraded to version 10.6.3 and I am still experiencing the same problem with my Logitech 960 USB headset.

I, too, upgraded to 10.6.3. The older 10.5.6 AppleUSBAudio.kext got replaced during the upgrade, and the static recording problem immediately reappeared.

I repeated the steps from cburgess on the previous page, installed the older 10.5.6, followed my addition steps on chown & chmod the .kext, and the input from the USB microphone is, once again, perfect.

I tried to follow the instruction from cburgess, but ran into problems.

step 4: make a back-up of the existing driver
result: cp: /System/Library/Extension/AppleUSBAudio.kext: No such file or directory
I checked the folder, and there is no existing AppleUSBAudio.kext file.

step 9: load the new downloaded driver
result: /System/Library/Extensions/AppleUSBAudio.kext failed to load - (libkern/kext) not found; check the system/kernel logs for errors or try kextutil(8).
The downloaded file is in my downloads folder.

Please help? Every 20 minutes I turn into ROBOPRIEST and it's getting old. I don't understand what booting in 64-bit kernel means, and I don't know how to run chowns or chmods.

I have a Mac Pro with 10.6.3.

there are errors in the commands which have to be corrected before using them.


Step 4 should be like this:

cp -Rp /System/Library/Extensions/AppleUSBAudio.kext ~/Documents/AppleUSBAudio.kext-BACKUP

Step 8 should be like this:

sudo mv ~/Downloads/AppleUSBAudio.kext /System/Library/Extensions/AppleUSBAudio.kext

I did this but reverted back to the original AppleUSBaudio.kext because I was getting Kernel panics when using the old kext.

I tried with the corrected commands, but I keep getting errors.

Step 4 error
cp: /System/Library/Extensions/AppleUSBAudio.kext: No such file or directory

Step 6 error
Can't open CFBundle for /System/Library/Extensions/AppleUSBAudio.kext.

Step 8 error
mv: rename /Users/USERNAME/Downloads/AppleUSBAudio.kext to /System/Library/Extensions/AppleUSBAudio.kext: No such file or directory

Step 9 error
/System/Library/Extensions/AppleUSBAudio.kext failed to load - (libkern/kext) not found; check the system/kernel logs for errors or try kextutil(8).

I checked the Extensions folder and there's no AppleUSBAudio file. The downloaded file is in my Users/USERNAME/Downloads folder.

I got as far as trying to install the downloaded AppleUSBAudio.kext file, and got this pop-up message:

"The system extension "/Sytem/Library/Extensions/AppleUSBAudio.kext" was installed improperly and cannot be used. Please try reinstalling it, or contact the product's vendor for an update."

The error message in Terminal is:
/System/Library/Extensions/AppleUSBAudio.kext failed to load - (libkern/kext) authentication failure (file ownership/permissions); check the system/kernel logs for errors or try kextutil(8).

And now I can't use my USB headset or speakers at all.

Open up diskutilities and run repair permission for the startup disc. restart the computer and then it should be good.

You might have to run the " sudo kextload /System/Library/Extensions/AppleUSBAudio.kext " command again once you have restarted your computer though.

Thank you for your help. I reinstalled the system because I needed to have sound working today, but I'll try your suggestion on the weekend.

Thank you

Seems like the latest update to OSX brought this back for me... so bump.

This fix did originally resolve the issue.. but since the latest apple update this fix no longer wants to work.. any suggestions?

I'm running 10.6.4 on my iMac i5 and I am having this problem as well over Ventrilo using a Logitech USB headset. Everything will be fine for 20 or so minutes, then out of nowhere my headset mic makes me sound like a robot. Pretty annoying.

Hoping Apple gets a fix in the works for this.

Same issue here. This is really annoying. We know this is a USB driver issue because swapping the USB kext for an older one worked. Come on, Apple, please address this.

Trev

I am running 10.5.8. I tried different devices such as USB headsets and lately connecting a Allen&Heath Xone 42 DJ mixer via usb to my Mac pro. this is top audio equipment, yet I have the same problem as with the headsets. My voice sounds robotic. I need this way of audio input to stream music online and play live shows on second life, I will have to cancel all shows if I cannot resolve this. Hey Apple people! thanks for the Iphone and the Ipad, I think you are all doing a great Job. but this minor problem seems to have been around for a while and a tough one for many users! why the silence about it! You are winning the war with microsoft but do you not have a cure for the flu? PLEASE HELP! DO I HAVE TO SPEND MONEY ON CALLING APPLE IN THE US AGAIN AND SPEND HOURS ON THE PHONE TO FIX THIS????? driving me mad I must admit! This mac did cost me a bomb and I need it for a living. please make it work!