I have my TCL 4k TV connected via HDMI ARC to Sony DH790 receiver. Recently I added my PC into the mix, but since then the HDMI ARC doesn't work. PC is connected via displayport to HDMI adaptor to the receiver (tried direct to TV HDMI input also), but since then the audio from the TV wont play through the audio receiver. HDMI adaptor fully supports 4K videos and 8 channel audio transmission. Appreciate expert advise on this. If someone has already solved this problem and posted a thread please provide me with details.