I believe your Samsung TV currently has ARC support but no eARC support. You'll have to wait until Samsung generates new firmware update for your TV to allow for eACR support.
These are the audio capabilities of the Samsung Q70R (I believe your TV is similar).
For all of us with Q70/80/90R soundbars and TV's that will not get the eARC update the only solution to solve the HD sound formats (dts, dts:x, HD-MA, etc.) Is a tv box. All these HD audio formats can be delivered to the soundbar from a good tv box via hdmi-in. Thats how solved this problem. Here you have a review on this https://www.rtings.com/soundbar/reviews/samsung/hw-q70r
All, i am reading this thread all the week and i want to thank you all for your feedback.
Since i still don't have an eARC TV (i am still on LG C7), i will simply skip this update. I suffered from the disconnection so much before updating to 1007.9 fw, now my config works like a charm and i will not take the risk. Good luck to all who updated to this last update and got those issues back :-(
I got my new LG CX set up yesterday and did have a little trouble getting eARC to show up even though tv was set to eARC. Ended up doing a resetting the hdmi handshake by power down and disconnect from power and then power on and connect hdmi. Works fine now.