Same thing happened to me with AT&T in Tulsa with their fastest offering (I think it was 24/3 at the time). All speed tests, downloads, uploads were almost always the advertised speeds, but I couldn't watch Netflix or HBO GO, or Hulu. I could, but it was unbearable. To the point of kicking over magazine stands and throwing Nintendo controllers at the TV.
When I called support about this they claimed it was my setup. A Time Capsule connected to their modem/router. Whatever.
I switched to Cox (100/25) and get better than advertised speeds in all downloads, uploads, and speed tests, and have not had a single issue with buffering on any service. I have even been choosing the 1080p option on YouTube without any buffering.
The only problem I have now is whenever my Time Capsule is directly connected to my Motorola modem it causes the modem to restart, so I had to use a slower, older Linksys in-between the two until I figure out what's the cause of that.
Similar prob with AT&T in SoCal, bad Netflix, Youtube, and actually, almost all large file transfers of any kind, including linux isos, apple dmgs & system updates, etc. Switched to an independent ISP carried over the same AT&T DSL lines and I could actually get the advertised bandwidth consistently.
I suspect the only reason DSL is accessible by third-party ISP is that it carries some regulatory access rules with it because only U-Verse can get to the higher tiers of bandwidth.
My broadband choices are lower speeds with third-party DSL 6Mbps, or higher speeds with AT&T U-Verse, or TWC both of which seem to selectively throttle competing video services like YouTube or Netflix.
When I called support about this they claimed it was my setup. A Time Capsule connected to their modem/router. Whatever.
I switched to Cox (100/25) and get better than advertised speeds in all downloads, uploads, and speed tests, and have not had a single issue with buffering on any service. I have even been choosing the 1080p option on YouTube without any buffering.
The only problem I have now is whenever my Time Capsule is directly connected to my Motorola modem it causes the modem to restart, so I had to use a slower, older Linksys in-between the two until I figure out what's the cause of that.