Is it a voice remote or a simple remote? If it's a voice remote, try resetting it by pressing and holding Home and Back (the two buttons next to each other at the top of the remote) for 20 seconds. I think you'll have to pair it again after it resets. That procedure won't do anything for a simple remote. For either type of remote remote, see if it's constantly transmitting. If the light on the Roku device is blinking even when you're not pressing a button, try removing the batteries and see if it stops. You can also see if a simple remote is transmitting by pointing it at your phone's camera. You'll see a flash coming from the end of the remote on your phone's screen when you press a button or if it's constantly transmitting.
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