I sometimes hear no sound when switching from the YouTube™ app to TV via the TV button.

Workaround

If the audio cuts out when switching from the YouTube app to TV, press the TV button on the remote control again to hear sound from the TV.

What causes this temporary audio loss?

Android apps need to acquire Audio Focus (the right to play sound) before outputting any audio. The sound may occasionally disappear if more than one app (e.g. YouTube, TV) acquires Audio Focus at the same time.

For example, on YouTube’s Home screen, if you highlight a video and wait for around three seconds, a preview of the video starts playing, and YouTube acquires Audio Focus at that moment. However, if you press the TV button right when the YouTube preview acquires Audio Focus, the TV app will also try to acquire Audio Focus at the same time. In rare cases, the timing may cause the YouTube preview to keep the Audio Focus instead of the TV app, which can result in temporary audio loss.