I have an old Denon 3806 receiver without HDMI arc. My TV is an Philips 58pus8545 android TV connected with optical. Netflix sends out 5.1 Dolby digital but I could only get stereo from Disney+ and HBO max. On a whim I ordered an 30 bucks HDMI arc extractor on Amazon. HDMI to optical/coax, ac3 and Dts 5.1 output. After ordering I regretted it, since I couldn't understand what difference it is would be to my existing optical output. But strange enough, it works. And the messed up part is that my existing optical connection sends out 5.1 Dolby digital from Disney+ and HBO max. In order to get it working I had to connect the extractor, then in the TV menu activate "HDMI sound system". My guess is that the activation, that I only can do with the TV connected to an arc HDMI, tells Disney and HBO that the system can play 5.1 and then proceeds to output that on both HDMI and optical . Maybe this fix only is valid for Philips TVs but I'm happy it's working and just wanted to share.