Denon 2300 receiver not playing 4.1 sound from Chromecast or Roku
I have a Denon 2300, and I have 4 speakers and one subwoofer connected to it. I am playing via chromecast or Roku, but I am unable to get sound from rear surround speakers.
When I run a test tone via Denon menu, I do get sound from them, but when I run a youtube video of Dolby test sounds or something, which plays sound on each speaker, I just hear sound from Front L and R speakers.
Also, when I press Info button on my remote, I see input signal as only FL and FR; and Active speakers as only FR, FL and SW. Rear surround speakers are shown as inactive.
Is there a setting somewhere I can set input as 5.1. I did set output on my roku to be Dolby Digital, but I dont think it changed anything.