I have a Samsung KS8000 and a Onkyo TX-NR545 receiver. I have the receiver setup using the HDMI ARC port and all the settings you suggested. However, I am unable to use the actual TV input that the receiver is connected to in order to display HDMI sources that are plugged into the receiver. The TV says that "this source I'd already set as a speaker". I am currently unable to use any HDMI/4k passthrough from my receiver to the TV.