I'm using a fire stick on my tv. I constantly need to sign in. The app randomly locks up. Strange video problems on the sign in screen. I've uninstalled and reinstalled and I'm still having problems. At this point it doesn't work at all.
Update: I reset my fire stick to factory defaults and it's more stable when loading the app. I still get an occasional error message but then I click on clear cache and it loads. I only had these problems on one of three fire sticks.