I finally upgraded my media room to 4K, installing these devices...
—Denon AVR-X4700H AV Receiver
—LG 4K OLED 77C1 77-inch Television (OLED77C1PUB)
—Panasonic DP-UB9000 Ultra HD 4K Blu-Ray Player
—Roku Ultra HDR 4K UHD Streaming Media Player (2020 Edition)
For now, I’m continuing to use the same DVR cable box (Arris 3600 Cable Box with Enhanced DVR (HD, 1080i box from Spectrum) and the same 5.1 Surround Sound speaker setup that had already been there.
All the devices are connected to my receiver.
I notice that, when I stream using the Roku device or via the apps that are built into the TV, my surround speakers are no longer engaged. They stay quiet, even for content that should have surround sound. For instance, I can watch a broadcast on my regular cable box that clearly uses my surround speakers. But that exact content, when streamed through the Roku or via the TV is in stereo only; no surround sound.
What is happening?
One thought: the TV is connected, using an HDMI cord, to the receiver’s HDMI Out HDCP 2.3 port. Is there also supposed to be a different connection to hear sound from the TV—or the Roku, for that matter—in surround? The Roku is connected to an HDMI In HDCP 2.3 port.