Netflix on Friday denied that it prioritizes the quality of its streaming service, and said that it is looking to resolve any issues by year's end.

"Our aspiration is to deliver to everyone the best bitrate that their broadband connection can support," Neil Hunt, chief product officer at Netflix, wrote in a blog post.

Hunt's post was prompted by blogosphere reports that Netflix's streaming "Watch Instantly" feature worked better on some devices than other. A person watching on their PC would have a clear picture, for example, while someone on their Xbox would get disruptions, or vice versa.

The problem is basically due to regional Internet congestion, Hunt said.

Streaming content is housed on content delivery network (CDN) servers that are located throughout the U.S. so that the movies do not have to travel as far to get to a computer, Xbox, or Roku player, he said.

Instead, the data travels via "regional and metro networks that have much higher aggregate bandwidth," Hunt wrote. "This means that if there is any congestion and slowdown, it will be different in different regions. Hence some customers may be affected, while others are not."

Different ISPs also have different ways to route their data, so someone with Time Warner Cable might have a different experience than a neighbor with Cablevision, for example.

Finally, devices like the Xbox and Roku may have different encodes that come from different CDNs - meaning they have separate paths or bottlenecks.

"Accordingly, customers may see better performance on Xbox than their PC, or vice-versa," Hunt said. "Equivalently, some titles may stream unaffected, while others suffer congestion. There is no purposeful discrimination between different clients - we want them all to perform very well."

Can Netflix fix this? Hunt said the company's engineering team is currently working to "multi-source" its content so that content can re-direct in times of congestion.

"Our newest Silverlight player (for Mac and PC) incorporates an initial version of multi-sourcing, and as we improve it, we'll roll it out to everyone including our device partners such as Roku and Xbox," he said. "We hope by the end of year to have this problem largely solved."