I'm running an Apple Airport extreme 5th Gen and a Comcast cable hook up. On my Macbook Pro, iPhone 5 and 3 iPads, I'm seeing speeds up to 60 mbps. I used to see the same speeds on the 2 4S's I have here, and after the update, both the 4S's wifi speeds drop to 0.1. Painfully slow. If I connect the 4S's to my Verizon MiFi, the speeds are fine again. It's only when I connect to my Airport Extreme, and only on the 4S phones.
On the Extreme, I've turned off security completely, that didn't make a difference. I've set up an open guest account, and that didn't work either.
On the phones, I've tried resetting the network settings, a restore and set up as a new iPhone, a DFU restore and set up as a new iPhone... Nothing works on either 4S.
I'm going crazy with this. I can't roll back the phones to 5.1.1, I don't think I can roll back to 6.0, so my only choice I think is to try to instal the Beta on one of them and see if that helps.
I'm open to any suggestions if you guys have any. I have two females in my house not happy, and they let me know it. haha. I currently have them on my MiFi at home, using up my 5 gigs fast... Ahhhhh First World problems. haha
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The Apple discussion boards have a 151 page thread on this issue. It seems I'm not alone in this.
https://discussions.apple.com/thread/4310121?start=0&tstart=0