Latest Plex Pass server update, client Apple TV 4K OS and client Plex app. The audio is silent, but the video played fine. Note, the audio plays fine on other Non-AppleTV devices with Plex app. Here is mediainfo for the encoded audio...
Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AAC / LC
Format settings : NBC
Codec ID : A_AAC-2
Duration : 1 h 10 min
Bit rate : 181 kb/s
Channel(s) : 6 channels
Channel(s)_Original : 18 channels
Channel positions : Front: 14, Side: C, Back: C, LFE= 2
Sampling rate : 48.0 kHz / 24.0 kHz
Frame rate : 23.438 FPS (1024 SPF)
Compression mode : Lossy
Delay relative to video : 23 ms
Stream size : 91.9 MiB (11%)
Default : Yes
Please fix. Thank you.