For me, turning off auto-play worked on both my Roku and Visio TVs. I actually turned it off on a per user basis.
As for the auto-playing previews, my partial solution is to hit the mute button when browsing the Netflix home screen. Still gets annoying when trying to read the text description of a show, but it disappears from the screen too fast and replaced by the preview.
As for the auto-playing previews, my partial solution is to hit the mute button when browsing the Netflix home screen. Still gets annoying when trying to read the text description of a show, but it disappears from the screen too fast and replaced by the preview.