Q: iMac 12,2 (mid 2011) airport (wireless) problem

Great to hear, that my solution works ;-) At least for some of you...

@Treme:

We are discussing problems with the new 2011 imac here only - your problem is completely different. We're experiencing dropped connections - not slow speeds. In my opinion, your problem is related to something very different i.e. broken antenna etc..

@Treme @completelyterrified:

This is not the right place for Apple-bashing ;-)

I'm no Apple basher - love their products, and own several iPads, iPhone, and this is now my 4th Mac. It's definitely appropriate to call a company out on a problem, no matter how much you love them.

I know you intended to be kind with your comment and not trying to start a flame war; but I think this is the perfect forum to point out when Apple is not living up to their reputation and obligation to create and deliver quality products. Because we all pay a significant premium to own their products we expect more from them in terms of responsiveness and service. In this case Apple is failing miserably in addressing and dealing with a significant problem.

Please don't take this comment as starting some thread crapping, just pointing this out.

Peace.

I've had my new iMac 21.5 for about 3 weeks.  Periodically, about 3-4 times a day, it loses its internet connection.  What is indicated if toggling the Airport off and then back on always restores my connection? 

I have cable internet and a Netgear wireless router.  I also have a 1.5-year old Macbook Pro that does not have this connectivity problem (on the same network).

I've got timeout problems with osx on my mac over wifi after 10 mins and I found this trick around.

I don't know it it could help but try these command lines (it's not permanent and it reset after a restart).

Terminal:

sudo sysctl -w net.inet.tcp.rfc1323=0

sudo sysctl -w net.inet.tcp.recvspace=32768

sudo sysctl -w net.inet.tcp.sendspace=32768

sudo sysctl -w net.inet.tcp.win_scale_factor=1

sudo sysctl -w net.inet.tcp.sockthreshold=0

hi BloomingSkull. I try you trick. but its now working. the connection dead after 10 minutes.

Anyone else tried Lion? I loaded the Gold Master and I believe the problem is gone.

Good... so next week on 13 july when we have lion will be no problem then...

my  iMac is brand new.. and this airport problem makes me really angry..

connection broke up after maybe every minute.. it`s a wonder if it`s stable for an hour..

tried all your stuff here and nothing works.. hope with Lion it`s all gone!

but good to know i`m not the only one!

OK - now I'm getting REALLY annoyed.  After not having any problems for at least 3 days I have needed to do the "turn airport off/turn airport back on" trick over 30 times in the past 2 days AND my new iMac won't burn a working DVD in Snow Leopard, when it will in Bootcamp (Windows 7) with the same media !!!

Hi Sodner,

can you still confirm that the WLAN issue is sustainably gone after updating to Lion? I've heard about cases with workarounds before in which the failure returned after several days so I wonder whether Lion reliably fixes the bug...

Regards

Christian

Hi DamenS,

I dodn't know the type of router you are using but in my case turning off the option to use 300 MBit channels did the trick. Since then I havn't got the faintest drop out problems anymore (for two weeks right now). The downside is that you can't use 300 MBit...

Give it a try if you your router offers the option!

Regards

Christian

Well I have been having the same dropout problems as well as problems with the wifi connection after sleep.  I run a 2nd gen airport extreme router WPA2 personal and both old and new iMacs as wells as MBPs on the network.  The new mid 2011 iMac was the only computer having the problems previously reported.  I tried every suggestion so far with no results (changing WPA to WEP, no security) Changing frequencies 2.4 and 5.0, clearing out keychain passwords for network, repairing disc permissions, and on and on.  Finally, and it makes no sense I set my Airport extreme to only broadcast in g, Airport Utility->manual setup->Wireless->and option clicking the radio mode to get option for wireless g only broadcast.  Drop out has stopped for a few hours so far and the no connection after sleep is no longer occuring.  Time will tell.  It is aggravating the new machine is performing so poorly, but hopefully the fix holds....

Does anybody know whether the reported WLAN connectivity problems of the mid 2011 iMac and/or the early 2011 MBP still occur in combination with the 5th gen AirPoirt Extreme released end of June?

Many of us seem to have WLAN connectivity issues with various non-Apple routers, others - like LOtang - face the same trouble even with AirPort Extreme/Express routers of the pre-5th gen. Therefor I wonder whether the bug still appears in combination with the new APE which enables 450 MBit transmission - as the new MBP and iMac do.

I have the same symptoms on my iMac 27" (mid 2011), all other wireless devices work fine with the router I use. I had initial good results today after manually changing the channel on my wireless router (I picked a random channel number), it was previously set to Auto. I was able to continuously stream a Netflix movie without stalling for over ten minutes. Previously it remained connected for only a few minutes before every network app on the iMac froze up. I'll know better results tonight but you may be able to fix this from your router. There may be many other wireless networks in your area that are using the same channel; changing the channel may help. Good luck.