For clarification, when you said that your TV is Roku supported, do you mean it has a Roku built-in to it? If yes, please be advised that remotes for Roku TVs are manufactured directly by the TV manufacturer. We would recommend reaching out to the TV manufacturer's customer support team to report the issue and get help.
I'm assuming this is not a Roku TV, but a TV with a Roku attached.
And, since you said "within 6 inches of TV" and not "within 6 inches of Roku" I assume you're talking about the remote controlling the TV. Therefore, I assume it's a Roku device that came with a Voice Remote. And, if it's in the current lineup, it's not a Roku Express.
If that's not correct, stop now and give us the correct details, to include Roku model number and TV brand & model.
The Voice Remotes pair to the Roku devices, so don't try to fix by re-pairing the remote. That won't help.
The Roku usually detect the TV and allows the Voice Remote to work via CEC. However, since you have to hold the remote close to the TV, that indicates the Roku didn't detect it, or at least, couldn't control via CEC, so it's using IR codes.
Have you ensured the end of the remote and the TV IR sensor are both clean and dry (don't use chemicals, just a damp cloth followed by a dry cloth to clean)? And, of course, that nothing is in the way. And don't forget the line of sight is from the end of the remote to the TV, not from your eyes to the TV.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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