Originally Posted by Alex solomon
The problem actually started when I selected 3.5 Mbps stream from the debugger screen. Initially it was set to auto. The PQ was inferior to what I was getting when set to auto, so I set the stream selection back to auto but failed to get the PQ I used to have. The material was the same. Heroes-season 3 in HD which has excellent video quality (near blu-ray quality as a matter of fact). I dismissed this as the cause, as changing the stream selection can't possibly change the picture quality permanently. Since that day every HD or SD movie I stream looks like crap even though Roku debugger indicated I stream @3.5 Mbps and I get four DOTS HD. I bought another Roku buy the problem is still there so I RMAed it back. I really don't know what else to do from here.
It sounds like you've eliminated the player as the cause since you've already tried overriding the stream selection, and even replacing the Roku box, with no improvement in picture quality. That appears to leave Netflix stream availability as the possible culprit.
Roku forum members have reported a number of scenarios where the HD streams became unavailable from the Netflix CDN servers. The causes don't seem clear and the HD stream usually gets reinstated sometime later although there's no outward indication of when or why the stream availability changed.
Note that the Roku stream override can only select the closest available stream quality. So if you choose 3.5, but the HD streams are currently unavailable, it will keep stepping down until it find the first available feed. Unfortunately, there's no easy way to see when this happens because using stream override also turns off the speed debugger display window.
How about other HD shows besides Heroes? Does The Office or Superman II also look bad (they both should have 3.8 HD streams)?