You may experience problems with ARC from time to time. With no real standard for a feature set and even a name across different manufacturers for HDMI-CEC, problems with ARC are common. Unplugging devices or performing a reset is common practice to get it to work again. Make sure to use an HDMI 2.0 certified cable rated for 18gbps. Non certified cables and those with say 10gbps ratings may work intermittently.