I have a similar problem in that when trying to watch a video using the browser it will sometimes freeze immediately or sometimes not freeze at all. More often it will freeze after a second or two into a video, sit for about 10 seconds and then the TV will reboot. This all just started recently as for the past couple of years of having the TV I could play video in the browser without issue. There was no update applied just prior to this and initially I thought it might be the content so tried a few test videos from various sources with the same results. I've gotten to the point I just cast from my laptop but it was nice to be able to go to a site on the TV browser and just play a video if one was part of the content.
