BUG: Mountain Lion kills wifi speed when using airplay or time capsule

Here is the 10.7.3 IO80211Familykext (version 4.1.2), if anyone wants it. It's been working great for me.

It works great gunny thank you.

thanks for the info - i think i will update my 2011 iMac (had not done so due to audio bug) since the audio bug is fixed I will see how I like X.8 then maybe update the MBP after I am done with the critical work I have to do for work done on it till i upgrade if i upgrade. I did a clean install of X.7 as i did not own OX.6 when i was given the MBP a year and half ago. I had to put $500 into it to make it work (ie apple replaced the logic board, top cover, backlight and the LCD for $300 and had to buy new battery and powersupply but the computer works like new alothough a little sluggish due to the 4 gig of ram and supper slow 200 gig hard drive. Overall i am happy with it as this replaced my 17" Powerbook - took a little getting used to the smaller screen. Since apple replaced the Logic board the computer has been running at least 8 hours a day 5 days a week for the past year and half with no hardware issues at all. Might wait till X.9 comes out and if there is no support for the 3.1 MBP then i will play around with X.8 - or if my work is done i will play with it soon just do not want to do a clean install atm as have deadlines with work.

Other than streaming to appleTV and the time capsule wireless backup are there any other issues with X.8 and wireless? anyone test with Airparrot, AirFoil or the older airport express?

Yorick,

When I first updated to Mountain Lion and noticed this problem with streaming music, I tried Airfoil and encountered the same issue. I haven't tried it since.

I wonder if anyone has any comments on my particular variant of this problem. I originally posted on this thread back on 5th Dec '12. I had recently "upgraded" to ML and had experienced the Time Machine and Apple TV issues associated with that OS version and my MacBook Pro 3.1. After a lot of investigation/research/reading I came across this thread that seemed the closest to my problem so I gave the kext downgrade a try and everything worked perfectly following the downgrade - happy days!

I follow the updates on this thread quite keenly, so I was aware that there appeared to be an issue with the 10.8.3 patch - so I was aware that I shouldn't be ugrading to that ... and so far haven't. Then recently, I noticed that my TM backups were taking an inordinate time to complete. My machine seems to be taking the same amount of time to backup now as it did following my initial upgrade to ML (but prior to the kext downgrade).

So, despite the fact that I've not upgraded to 10.8.3 I seem to be back where I was ... any ideas?

Also, I'm a little unfamiliar with workings of these kernel extensions and how to manipulate them etc. etc. - how do I check I'm still using the correct kext that I reverted to back in Dec '12? Maybe, even though I've not upgraded to 10.8.3 something else that I may have upgrade to has altered the version of that extension under the radar.

wattersd,

To find the version number of the installed kext (IO80211Family.kext), use the Finder's "Get Info" option on the kext in /System/Library/Extensions or use Kext Wizard (part of the kext package linked to earlier in this thread). With Kext Wizard, you can use the Kext info option to or the Loaded option to find this info.

If the kext version is 5.0 or higher, you have the buggy version from Mountain Lion installed. If it's an earlier version, report back here which version or just reapply the kext downgrade using the version I provided in the download link.

Also, it would be a good idea for you to run Kext Wizard's maintenance routine (repair permissions and rebuild cache) on /System/Library/Extensions.

The OS X 10.8.3 update works great. Might be easiest if you just apply the 10.8.3 combo updater, followed by the kext downgrade. Then check the kext version number after that.

Hi Gunny,

Thanks for the all the info - much appreciated. Bulding on yours, and others, experience with this issue has saved me (and I'm sure others) lots of time and aggravation.

I used Finder's "Get Info" as you suggested and it tells me it's v3.2 - so I'm not sure what's gone on to kill my Time Machine back ups.

As you've suggested 10.8.3 seems to be working for you (following the kext reversion). I think I'm going to give that a try (after a good disk clone). Then I'll revert the kext to v4.1.2 to see how that goes.

Thanks once again - I'll report back on my results.

David.

If you're still having Time Machine problems after updating to 10.8.3 and reapplying the kext patch, you might want to see if the problem is with your Time Machine backup. Run Disk Utility on the backup drive and also do a "verify" of the backup. You won't find a better or more complete collection of Time Machine troubleshooting tips here: http://pondini.org/TM/Home.html

So ... I applied the 10.8.3 patch, then, using the Kext Wizard, reverted the WIFI kext (this time I went to straight to v4.1.2 as opposed to the v3.2 I was on) and all is looking good.

Thanks for your hints and tips Gunny.

David.

I can't believe this worked. For months I have struggled with this on my 2007 Macbook Pro. Now everything is backing up smoothly and airplay is seamless. Thanks everyone.

I can't believe it took a clever user to figure out the solution. And, I can't believe so much time has elapsed since the user found and fixed the problem, and Apple STILL has not fixed it in a patch. Pathetic. My next laptop might not be Apple!

Has anyone tried the new ML update 10.8.4 and does it break it again?

Not yet, but I'm going to guess that the bug hasn't been fixed. Just a cynical hunch. Anyway, we'll find out soon enough.

Nope, not fixed.

😠

Obviously not a high-priority bug for Apple or perhaps they haven't received enough bug reports. If any of you haven't yet, please submit a bug report to Apple describing this problem.

And if you've already updated to 10.8.4, just re-apply the WiFi kext from 10.7.3.

10.8.4 breaks the wifi fix thanks to a change with the drivers. However, I have a fix which makes it work again. :-)

You need the /usr/libexec/airportd from 10.8.3 to replace the one in 10.8.4. I'm sure this undoes some bug fixes and stuff done to the wifi support in 10.8.4, but until apple fixes the wifi problems....

Get it here.

1. Turn off wifi.

2. sudo mv /usr/libexec/airportd /usr/libexec/airportd.old

3. sudo cp airportd /usr/libexec/airportd

4. Turn on wifi.

5. Happy!

Brielle

briellie,

Can you specify exactly the problem? Is it that while streaming and time machine or capsule backups start on the wifi network that the wifi speed for other things drops dramatically? Or what? Does it have anything to do with dropouts on audio streaming? I am confused.

Nate