As expected, Samsung washes its hands from any liability. With the help of Stephen Withers, they misled us all, and now they say they can't speculate about anything. Throughout the past year they have speculated using Whithers and his websites, where he writes reviews. Disgustingly biased and hypocritical reviews without ascertaining the actual parameters of the device.
I recommand also publishing the link to this reddit page, the comunity page and this twitt on all the Home Theater forum you suscribe to.
If we want another answer than these "I don't know" and avoid Ruty to bury the subject, we need to make a maximum noise
I also ended up returning this just within the period. Disappointed but relieved, all the confusion n deception, and lack of action or response from samsung regarding earc. Anyway with new sb's coming this year, there's some interesting options with these features and earc or hdmi 2.1
I was in the same position wanting a premium soundbar with eARC support to complement my Sony TV 85G. looked into the top of the range Samsung Q90R, JBL and Panasonic but none supported eARC. Lucky I came across this forum before purchase. I even went to my local hifi store in Sydney, the salesman said yeah the Samsung supports eARC, but he had no idea, as I already knew that it didn't based on all the info I have read. Its not a good look for Samsung, it really should only be a software update. Anyway I ended purchasing the Sony HT-Z9RF sound bar, Im glad I did, it supports eARC like most Sony soundbars, no issues with lip sync, sound is awesome what you would expect from a Sony product, comes with satellite rear speakers as well, online firmware updates, no need for USB to update firmware like some soundbars. My advise is to check out the Sony Soundbar range, you wont be disappointed.