Apple Releases Second watchOS 26.4, tvOS 26.4 and visionOS 26.4 Betas

Does anyone know what that continuous audio option actually does?

I wish it was true audio passthru but it would have been reported on by now if it was

Keeps a persistent HDMI audio signal alive, even if no audio is playing. So instead of dropping the connection or switching formats, it will just be one continuous audio stream. An example would be when switching from stereo to 5.1, where previously you'd have a short audio interruption or if you pause an 5.1 audio stream and replay, again, you'd have a new handshake and short lag in audio coming back. This should also solve some issues where multichannel PCM content was quieter on some systems (e.g. Sonos).

This is not passthrough. In fact you will now see things like a consistent "Atmos" signal even when non-Atmos content is playing.

I will also note that, having tried it, it also makes multichannel 5.1 content sound better at the same relative volumes on Sonos (punchier, more precise bass/LFE effects, better soundstage). I'm not sure how wrapping it in a Dolby MAT container fixed that, but I'm not complaining. Apple always claimed that converting everything to LPCM had no change on the output sound ... maybe that is true for sound leaving the Apple TV, but it's not true for sound being played back by my soundbar. Never had an issue with audio from my TV's apps, just Apple TV. I submitted multiple feature requests over the years asking for passthrough to solve this, and this feature somehow does, even though it isn't passthrough.

Does anyone know what that continuous audio option actually does?

I wish it was true audio passthru but it would have been reported on by now if it was

Keeps a persistent HDMI audio signal alive, even if no audio is playing. So instead of dropping the connection or switching formats, it will just be one continuous audio stream. An example would be when switching from stereo to 5.1, where previously you'd have a short audio interruption or if you pause an 5.1 audio stream and replay, again, you'd have a new handshake and short lag in audio coming back. This should also solve some issues where multichannel PCM content was quieter on some systems (e.g. Sonos).

This is not passthrough. In fact you will now see things like a consistent "Atmos" signal even when non-Atmos content is playing.

I will also note that, having tried it, it also makes multichannel 5.1 content sound better at the same relative volumes on Sonos (punchier, more precise bass/LFE effects, better soundstage). I'm not sure how wrapping it in a Dolby MAT container fixed that, but I'm not complaining. Apple always claimed that converting everything to LPCM had no change on the output sound ... maybe that is true for sound leaving the Apple TV, but it's not true for sound being played back by my soundbar. Never had an issue with audio from my TV's apps, just Apple TV. I submitted multiple feature requests over the years asking for passthrough to solve this, and this feature somehow does, even though it isn't passthrough.

I really wish they just just add true passthru. It would kill blu ray discs well and truly