This issue is a classic motherboard problem of this model. Quite a number of units were affected by this issue. If your phone is in warranty, claim warranty. Service center will replace the motherboard. If it is not in warranty anymore, then reflowin...
The same happened with me. I have tried clearing cache of UI as well as settings. It gets fixed for sometime and then randomly, issue comes back again. Turning the double tap to wake off then on or rebooting the phone temporarily fixes it.
I updated via FOTA yesterday and can confirm this. NetFlix or Amazon Prime not playing in full HD. Some previous bugs have returned also. SD card sometimes not detected on reboot/startup, recent apps disappears but comes back on launching a different...
