I've recently faced the problem that my Radeon RX 540 (embedded into Intel NUC NUC8i3CYSN) is unable to output more than 2 channels of audio when connected to a TV via HDMI and Windows's Speaker Setup settings has 5.1 and 7.1 muted.
I can output 7.1 or 5.1 directly to a capable AV receiver from Radeon RX 540, but only 2.0 sound to a TV in spite of the fact the TV passes the sound to 7.1 AV receiver.
That's because audio driver limits the output according to a connected device capabilities. It understands that the device is a 2.0 TV but it doesn't see that the TV itself fully delegates the audio to a 7.1 AV receiver.
It is a PC only problem. Any dvd/bd/media player connected to a TV that I was able to test outputs the correct number of multichannel audio to AV receiver through TV's HDMI ARC passthrough feature.
May I please kindly ask the developers to allow override this stupid limit via Adrenalin settings like it is possible to output a video resolution higher than the monitor possibilities. Of course at user's risk, as always.
Or may be someone knows and is willing to share the Windows registry key I can edit to get rid of this limit.
Many thanks in advance.