It could either be a faulty IR source in the remote, or a faulty IR receptor in the Roku device itself.
If you point the remote at the camera in a phone it should show flashes on the phone screen when you push the remote's buttons. Compare the flashes with flashes from known working remotes to see if there's a significant difference in brightness.
If the problem seems to be the remote, replacement Roku IR remotes can be found at Best Buy, Wal-Mart, Target, Amazon, etc. Just be sure it is a remote for Roku DEVICES, not Roku TVs - Roku TVs use a different set of IR command codes. Many inexpensive universal IR remotes have codes built in for Rokus devices as well.
You can also install the Roku app on your cell phone and use it to control your Roku as long as they are both connected to the same home network.
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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