So I have this weird problem with surround sounds. I have HW-Q76R soundbar with SWA-8500S rear speakers. I have connected my TV (UE65NU8005) with HDMI-ARC. I test my setup with Netflix's Test Patterns video. I have tried to change digital output settings with no luck: with PCM I get only stereo sound (I hear same sound from soundbar and rear speakers). When I try Dolby Digital or Dolby Digital+ I don't hear anything from rear speakers. However if I change soundbar connection to WIFI and use Dolby Digital, then everything works fine.
I have also PS4 connected directly to soundbar with HDMI and surround sounds works great with PS4's Netflix app.
Any idea what's wrong with my HDMI-ARC setup?