If you have a fast Internet connection but are still experiencing low-resolution movies, consider the following:

-       Bandwidth — Is there any other online activity on your network, like online gaming, file sharing or other video streaming that might be affecting your bandwidth? If you are on an unsecured wireless network, you may be unknowingly sharing your connection with other people in your area. Or, your ISP could be delivering a slower speed than advertised. You can test your bandwidth at one of these sites: speakeasy.net/speedtest or  www.speedtest.net.
  If you are getting less bandwidth than expected, you should contact your ISP (Internet Service Provider) to troubleshoot.

-       Router settings — If you are connecting via a wireless router, disable any Quality of Service (QoS) settings in your router setup. QoS helps police the traffic on your network letting more time-sensitive or critical traffic take priority over non-critical traffic. A common example would be VOIP traffic. Details on disabling your QoS setting can be found in the user manual for your router. You may also need to change the wireless channel on your router. If you live in a dense residential area, you may be able to see other wireless network around you. It is usually advisable to try and stay on a separate channel from them to avoid interference and noise on your wireless network. The 2.4Ghz spectrum used for 802.11 is divided into 11 channels in the US. Each channel is 22Mhz wide, and offset by 5Mhz to the next channel. Because of this, there is overlap on neighboring channels. Channels 1, 6 and 11 are commonly recommended as they have no overlapping frequencies. Details on changing the wireless channel setting can be found in the user manual for your router. In some cases, you may need to update your wireless router's firmware. Check with your router's manufacturer to verify that the latest firmware version is installed.