By "watching tv" do you mean you are watching something via a Roku device connected to your tv and it exits what you are watching and returns you to the Roku device's home screen, or do you mean watching on a Roku TV and it exits what you are watching and returns to the Roku TV home screen?
If you are watching on a separate Roku streaming device, is it powered by plugging it into a USB port on your television? The ports on many televisions only supply 0.5 amp or less, which is not enough to power a Roku reliably. Even if a Roku connected this way appears to start up normally, if it runs into an activity that requires more power than the USB port can deliver, something will fail, commonly taking you back to the home screen. It's possible the Roku update consumes a bit more power than before, which may require more than a barely-adequate power supply can deliver.
It is recommended that you power your Roku device via the power adapter that came with it, plugged into your house power. If you no longer have the USB power adapter that came with your device, you may have another one handy from another device that can be used -- just make sure the tiny print on it confirms it has a 5 volt dc output of at least 1 amp.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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