I had exactly the same problems as above, where the firestick 4k is concerned, make sure you have the latest very firmware installed and then turn off the default setting in the latest Plex Firestick app to transcode interlaced tv, this worked for me! Earlier firestick 4k firmware had a problem playing interlaced video (older firesticks & the later fire tv cube never had this problem!) I believe plex introduced this new option to transcode interlaced media, to help the 4k deal with this problem, but the latest firestick 4k firmware cures this problem anyhow. now this option seems redundant & if left in its default of switched on, then it causes the problems above i.e.bombing back to tv guide after 3 mins or so & loss of dashboard details etc. Turned the option off in the app options now everything working as it should. Hope this info may help somebody else…
