I have Roku Premiere+ on a Sony KDL-46W5100 (from 2009) tv that seems to cause Sony to reboot constantly. The back of the tv seems to be hot. It seems to do this when we are not streaming and maybe sitting on Amazon app or some other channel (after doing about an hour or more of streaming on amazon). The only fix is to turn off tv and turn on ceiling fan and wait about 4 minutes. It only started doing this within last six months. If I recall I believe philo also seems to have issues, so it's not just one app.
I don't have this problem with cable box or a computer that is connected to an hdmi port.
model 4630x Serial YR002A780110 software version 9.0.0 build 4142-29
auto adjust display refresh rate disabled hdr subsampling 4:2:2 (it's a 1080 tv anyways)
display type 1080p tv (recently changed to this to see if it fixes the problem, but did not)
There's nothing in an external device connected to an HDMI port that can cause a TV to overheat. I really doubt the Roku is causing it. Try the Roku and the cable box in different HDMI ports, especially the Roku in the port the cable box is currently using without a problem. My guess is the TV is going, and since it's 10 years old that's a strong possibility.
Dan Roku Stick (3600), Ultra (4640), Ultra (4670), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.