Choose the television edition
Search for the publisher’s app on the Android TV device itself. A phone screenshot in a web listing can be helpful, but it cannot tell you whether your remote can reach the controls. After installation, use only the remote to focus Search, start a channel, open the audio selector, toggle captions and return to the guide. If a control requires a touch gesture, ask whether the publisher has a dedicated TV edition.
Decode capability belongs to the model
Android players can use Media3 and system decoders, but manufacturers ship different decoding hardware and app developers expose different formats. Record the model, Android TV version and app build. Compare a short, known-good H.264 item with the trouble item if your service identifies their formats. If audio is fine but the screen is black only for the latter, the next useful detail is the codec or HDR profile, plus the device model.
Keep a usable channel guide
Set the TV to its actual timezone, then compare the app guide with the broadcaster schedule for one known programme. Verify a second channel before changing global guide offset. If one channel is wrong and others line up, the guide association may be the culprit. If all channels move together after a clock correction, keep the original source and document the setting that fixed it.