I just bought a new 4K TCL tv with 1 HDMI (arc), 1 optical, and one 3.5mm jack. All output. Im trying to connect this tv to my old Kenwood reciver that only has rca ports. I tried 3.5mm to rca, no luck. I tried an expensive hdmi arc extractor with rca outputs, no luck. The only thing left is optical. Am I doing something wrong? I’m so frustrated. Help would be appreciated, thanks !