Some Amazon Prime shows only showing audio/subtitles but no video

The Amazon Prime Video app for ATV lists a bit of info about a program's audio in little numbers and symbols like 5.1, "AD)))", etc. Older TV shows seem to show nothing (probably 2-channel stereo only). Do you see any such label consistently on your mute programs?

You said "Using an Apple TV 4K with a Sony.". Just a Sony TV? Which model? A Sony receiver or soundbar connected? More details please about your setup and its potentially audio-related settings.

Anyway, having quickly scanned Google search results on Prime & ATV audio issues, I'm suspecting a mismatch between your TV's settings and the ATV's settings - the ATV4K is sending the audio of certain shows in a format that your TV (or whatever else is connected to it) doesn't understand. Such issues usually won't occur if all of the HDMI CEC (Consumer Electronics Control) settings on all components are fully enabled. Sometimes these settings refer to specific HDMI ports, are buried under advanced menus or disguised under goofy marketing monikers (Sony's been known to refer to HDMI CEC as "BRAVIA Link" or "BRAVIA Sync"). The ATV4K sports most all of the latest & greated AV tech, so make sure the Sony has all auto/advanced HDMI / Audio / Video features turned on!

On the ATV4K, verify that Settings > Remotes and Devices > HOME THEATER CONTROL: Control TVs and Receivers = On. The ATV's Siri Remote should also control the system's volume automatically.

cosme,

Understood. It could be an issue with their content, though, since it's only happening with certain series. Content issues should be reported to the owner of the content, which in this case would be Amazon Prime. This is why we referred you there, initially.

If you were experiencing streaming issues with multiple channels on your Apple TV, you could try the following:

Restart Apple TV 

Update Apple TV software 

Best regards.

Hello cosme,

Since this issue is happening intermittently with series on Amazon's service, we recommend contacting them directly for steps to resolve this behavior: Prime Video

Regards.