Setup: Actiontec Rev I Router: 50 foot Cat5 cable to Roku XDS device. Speed test always indicates 50MBS download speed.
Netflix streaming has always worked but quality level varies and rebuffering and downgrading usually occurs. I'm often able to start out with 4 dots (highest streaming rate and quality) but often rebuffer and downgrade to 3 or 2 dots. With Roku set to debug, the stream speed is dropping when this occurs.
Amazon seems fine or, at least, much better.
I assigned the Static DNS address recommended by Roku. No help.
Netflix and Verizon (and other ISPs) have been engaged in a peering dispute for sometime. There has been a lot of talk about it on the net and also on the forum If you want to read about it the following link is a good start. Follow the links in the article for more info.
Also, Verizon users aren't the only ones who complain about slow speed issues on Netflix. Netflix is a very popular site and the heavy traffic load will be a problem during prime streaming hours. Time of day makes a difference. Where you are effects the route from you to the Netflix server and can effect speed.
I should point out that the article Walt referenced heavily mentions Cogent. Netflix is largely using Level 3 now which is a tier 1 provider just like Verizon. Even with Netflix using premium transit like Level 3, there are still issues with Verizon and other ISPs that have an interest in their own streaming alternatives like Verizon's Redbox Instant... My guess is, Verizon has no interest in increasing capacity with Level 3 because of why capacity needs to be increased even though they should have settlement free peering.
Install the speedtest channel on your Roku and then test using this App. Speeds are usually lower.
If you have a router using DD_WRT or Tomato they will let you monitor your download speed in real time. Useful for seeing what is actually happening.
I have encountered this same issue and it is annoying! If I try to load a Netflix video it loads and buffers very slowly (and no HD). If I connect to a VPN service first then watch Netflix it loads really fast even with HD video. I wish Verizon would stop intentionally slowing Netflix traffic.
Do you mean the Roku debug feature which shows connection and streaming speed? I've done that and the speeds degrade which watching for an hour or less. Is this a measure of total bandwidth or just the particular stream for Netflix? Obviously the stream has issues.
Netflix by itself accounts for about 1/3 of downstream traffic on the internet and is a competitor of the major ISPs. FIOS has Redbox, Comcast has Xfinity TV, etc etc. There is a ton of money at stake here and the ISPs are going to do the absolute bare minimum when it comes to Netflix.
There is a Speedtest channel for Roku. If you can't find it in the channel store then check a listing of private channels.
The best solution to see what is happening is use a router/AP that graphically plots bandwidth in real time.
If you're have issues this evening, it's probably due to reasons like below. I'm impressed with how high the latency is at the last ALTER.NET hop given that it's within Verizon's network.