I have my SM9000 LG EArc plugged into my Yamaha RX-A3040 Arc HDMI connection without any issues with pass through enabled on the LG. I too am using the TVs HDMI ports for switching much the same as the OP. The RX-A3040 doesn't support HDR so it only does audio duty. I see the OP had the same problem I had initially with the Yamaha labeling of A/V connections. Glad to see it got sorted out.