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Test your internet connection at https://www.speedtest.net/ . In order to view content on SelectTV you will need to have a connection speed of at least 3 Mbps.
Pause the video until after the buffer is fully and then try playing it again.
Close all other applications you have open and don't currently need.
Try clearing your browser cache and then refresh the page.
Try lowering the video quality settings if possible (depending on which player is being used).
Lowering the quality will reduce the processing demand on your computer or device. You will likely find this option near the bottom right corner of the video player.
If you are trying to watch a video through a wireless connection and the video keeps stuttering, try a wired connection, or try moving your computer closer to the Wi-Fi router to get a better signal.
Try playing the video in a different web browser to see if you experience the same problem.