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I also had slow youtube loading issues on my iPhone 4, iPhone 3GS, and iPad. I found a suggestion to change the DNS setting to OpenDNS (208.67.222.222, 208.67.220.220) and that mostly solved the slow loading issues for all three devices on my Wifi network. I still occasionally run into slow loading now and then, but it seems to be related to specific videos since other youtube videos will play fine.

http://www.opendns.com/

Can't hurt to try. Just change the DNS in the iPhone's Wifi settings.
 
I also had slow youtube loading issues on my iPhone 4, iPhone 3GS, and iPad. I found a suggestion to change the DNS setting to OpenDNS (208.67.222.222, 208.67.220.220) and that mostly solved the slow loading issues for all three devices on my Wifi network. I still occasionally run into slow loading now and then, but it seems to be related to specific videos since other youtube videos will play fine.

http://www.opendns.com/

Can't hurt to try. Just change the DNS in the iPhone's Wifi settings.

I've been on opendns for a long time and have this problem.
 
I've tried EVERY "solution" and nothing has worked. Thankfully I found this link which IS the only solution:

http://appletoolbox.com/2010/05/ipad-slow-youtube-fixes/

Tap Settings
Tap Wi-Fi on the left-hand side
Tap the blue arrow next to your current Wi-Fi network
Tap the “DNS” field and enter the following: 208.67.222.222, 208.67.220.220
Exit Settings"

I copied and pasted that from the Apple Support forum where I found it. The DNS settings above are from http://www.opendns.com which is a free DNS service that speeds everything up, especially Youtube. It went from unbearably slow, unreliable and intermittent to purring like a kitten and loads instantly every time now. Try it. It works. All the other stuff (changing encryption, changing/rerouting ports, turning off encryption, etc.) is all a waste of time.

I've been on opendns for a long time and have this problem.

Are you using Open DNS in your router or are you putting it in the iPhone for each Wi-Fi connect you use? I think you need to put it in the Wi-Fi settings on the iPhone for it to be effective.
 
depends on the wifi connection

AT&T probably has a dedicated fiber connection straight to Google/Youtube so you don't even have to go through the internet. on wifi it depends on the ISP and how the traffic is routed
 
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