Why 24fps is not enough for HDR movies

[shawn.malligan]

Hi

I’ve downloaded the June 2021 update for my Sony X9000H and it’s connected to my Yamaha RX-A2A AV Receiver via optical, hdmi 3 and 4. When watching TV, Disney +, games or movies via optical my sound switches back from the Yamaha back to the TV speakers on their own. I use settings to change it back but it switches back again. Is there a setting I need to use because on my previous Sony or other brands I never had this problem?

Thanks from Shawn