This seems to be an ongoing issue with the 4K Fire products. I have the pendent. It works for a while, then it updates and it no longer works. Netflix was not supposed to be working with Atmos, as it's only available with a few OLED TVs, a Japanese only streaming TV box, Apple TV 4k box, Windows 10, and 3 of the X Box models according to their website. As of today, it's in the No Atmos Mode, and I'm ready to just throw it away. I only bought it for the Dolby Atmos sound, and I wish I had never wasted my money on it. I'm sticking with Roku. It doesn't pass Atmos on Netflix, but at least it has the Vudu app, which Fire products don't even offer, and Atmos DOES work with it.
Having the same issue on my Fire TV Stick 4K, updated to latest firmware. Onkyo NR575 receiver. Doing all of the things noted above (watching the UHD 4K version of "Jack Ryan," waiting a few seconds, trying to manually select "Dolby Atmos" audio source but only "Dolby Digital+" and "Stereo" are available.) One note: my TV only supports 1080p video, but i'm setup for 5.1.2 Atmos audio.
Contacted Amazon Support today, they indicated that this is still a "known issue." Folks who are having the same issue, please update the thread if you get a resolution/update.
Yes, have the same issue. Cube, when set to my Atmos Soundbar, does provide Atoms option in menu and soundbar and does switch to Atmos.
When I use the Fire TV 4K it only shows Dolby + in the audio menu when watching the movie. However my sound bar does swith to reflect Atmos when starting the movie. So looks like the Fire TV 4k has a firmware glitch in the menu, but is passing Atmos.
Latest 4K Fire Stick, audio is only available as Stereo or Dolby Digital Plus. Interestingly, my Sony HTST5000 soundbar (which it's plugged into), after 30 seconds does say Dolby Atmos - Dolby Digital Plus 48kHz.
Tried starting the Video first & Still dont get any Audio Option for Dolby Atmos. Only get options for Dolby Digital Plus & Stereo. I have a 1080p TV, so I hooked up FireTV directly to my Atmos AVR, but it looks like need to have a 4K TV to get access to 4K UHD Version of Jack Ryan with Dolby Atmos thru the ARC on TV. This disserves the whole purpose of a FireTV 4K stick for me as a new 4K TV will have the Built in Smart Apps anyway.
Unless Amazon can find a software update to fix this issue soon, I will have to return my FireTV 4k Stick. May have to try Apple 4KTV as I'm not ready to buy a new 4K TV
I have a Vizio m65-eo, with a Vizio 5.1.2 atmos soundbar and I'm not getting the atmos option on my fire stick 4k with Jack Ryan or the Netflix app. Atmos comes through on my Xbox one s, but not my fire stick 4k. Only Dolby Digital + and stereo. Hopefully it's a firmware issue. I didn't spend all this money to choose atmos/no Dolby vision on my Xbox one s, or Dolby vision/no atmos on my fire stick 4k.
My current version after doing a reset is still OS 188.8.131.52 date 8/12/18 and wondered if there should be an update by now? My Dolby atmos still doesn't work and have given up corresponding with Amazon support. They don't even respond now.
Have exact same issue as others, no Dolby Atmos. Have an TCL 65R615 using HDMI ARC to TX-NR676. (Onkyo receiver just blinks on Dolby Atmos)
I've tried Amazon 4k Firestick + TCL(Roku Amazon Video App )+ Sony 4k DVD player(amazon Video App) However, I do get sound with with Apple TV 4k(not sure if it's Dolby Atmos though, will need to check that.