hdmi arc stopped working properly after oreo 8.0 update. Update installed with usb, factory reset after update and all settings adjusted ok. ARC works ok if tv shut down with long press power button, or power cable off. But after normal press of power button (goes to standby) arc doesn't work. I use Yamaha RX-V683 with latest firmware, absolutely 0-problems with arc in this setup in nougat 7.0. Bravia sync is on and doesn't matter if disabled, didn't help either to reset hdmi-control in yamaha settings. I noticed that when I put tv to standby, amp says "mute on" then "mute off" and then it shuts down. Amp always powers on after tv powers on, so bravia sync / hdmi control works ok.