There is a pairing process for the TV. You don't actually enter a code, but rather pick the TV manufacturer from a menu, the system will play music, then ask you if it stops. There may be multiple settings for each TV, so picking the first one that mutes the music isn't always the right one. It can get a little tricky when trying to bypass a partially working setting. But try to find the pairing setup under Remote in the menu system of your Roku.
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