Bizarre AppleTV fourth gen Audio problem  



I have a 4th gen Apple TV connected to a home theater receiver via HDMI. Yesterday, it was all working fine. Today, when I went to use it, I couldn't get any sound. Video was fine. But no sound anywhere.

I went to Settings and found that the Audio Output setting was blank (I don't know if it was like that before). When I went to select a sound source (which I assume was supposed to be Apple TV itself), it wasn't listed. Only AirPlay options were listed.

Any ideas what is going on?

[On a probably unrelated note, I happened to check the HDMI Output video setting and noticed that there was no YCbCr option; only RGB High and RGB Low. Is this supposed to be that way?]

This topic was modified 3 weeks ago by tedlandau

I’ve run into this with various HDMI devices, Apple TV included. It’s probably related to a bad HDCP handshake.

HDCP is a protocol that confirms a secure connection between audio/video source and destination, ensuring that no device is in between that could hijack the signal and grab a perfect digital copy of the data stream.

Usuallty unplugging and replugging the cable is all that’s needed to reset the connection and perform a new handshake.


Hi Dave. Thanks for replying. And congrats on your move from Facebook to here. Good decision!

As to the AppleTV problem, I doubt it is what you suggest (I wish it were!). As it turns out, I have a second AppleTV in another room. It's working fine. So I took that ATV to the setup where the problem was, disconnected the problem ATV and installed the working one (using the exact same cables as before). The newly installed ATV continues to have audio.

Thus, the problem is restricted to one specific ATV — not any cables or any other components. Restarting ATV had no effect BTW.

To me, this suggests a hardware problem, which means a dead ATV that needs to be replaced.


Ahh, yes. That could indicate a bad HDMI port on the affected Apple TV. You're right — the HDCP/HDMI handshake issue would be mitigated by simply removing and reinserting the cable... if it were just that.

It still could be an HDCP handshake issue, but perhaps caused by a fault HDMI port on the Apple TV. Maybe check to see if there's anything mucking that up in there?