The problem still is the route from the server to you. If one service takes a different route to deliver the stream, which of course it will, the bandwidth might be fine in all segments of that route, and you will have a clean viewing experience. If, however, there is a bottleneck in any segment of the stream, that will screw up packet delivery and the ultimate channel delivery
Now, I'm not saying this as a pie-in-the-sky analysis, because I'm experiencing the same issue. My HD channels (CNN, MSNBC, ESPN US, NESN, etc.) buffer quite often. I couldn't get a clean game the other night while watching NESN, but I found the same game on an HD feed from an add-on and it was hiccup free for the entire game.
My PC has the same issues as my device, so it isn't a device-driven problem. Let's hope and wait and see. I wish I had the answer, but I don't. I just tell it like I see it.