Recently I notice my Q90c and Q 990c are not co-operating. It only allows me to use wi-fi or blue tooth. I have been through the gamut for 2 weeks in every way possible, even with Chatgpt +. Just to be thorough, I have copied and extracted updated files to usb in every combination possible - NOTHING WORKS! The Q 90c does not recognize the Q-990c via eArc, even with factory data reset in the tv. Everything has been unplugged in every way imaginable; new HDMI cables; various HDMI cables. I have been in and out of every menu, in every way, clicking every switch in every combo I can think of - This is clearly on your end SAMSUNG. I am currently, setting the tv up as new and it does not acknowledge the soundbar as powered on when it is powered on. It picks up on any other device, but the Q-990c. This is a $5,000 fail and I am beyond livid. **bleep**?!!!