no sound on apple tv through projector

Hi Tanaka, that was a 'best guess' -- the audio codec negotiated with the streaming service is not a codec the Projector understands. CI was hoping the change to the audio settings in the Projector would be the issue with quickest fix.

With that not bringing about any remedy to your issue, here are my assumptions:

-Projector has a built in speaker system?

-Audio is being delivered AppleTV HDMI->Projector?

If correct assumptions: You noted all movies work properly when the AppleTV is connected to a TV. So presumably AppleTV and WAN side connection are doing what it needs to do.

-Assumption is the Projector isn't processing the audio it is receiving.

My next suggestion would be a compare. Choose a movie that is working and a movie isn't working. Play each and review what Audio info the projector will give you (on some TVs the info button will give you some A?V info). What's different?

I’d look at the projector’s audio settings. I believe a stream can have multiple audio type track options that are carried (or possibly one of them is negotiated at initial connection). The projector audio is capable on some audio types but not on others.

If there is a PCM option, give that a try. I believe Dolby re-encode is an option I’ve seen and would try.