sound streamer / receiver

The Trinnov Altitude 16 with the latest HDMI 2.1 board will accept 8K and can output digital over optical or coaxial for some of the channels.

Otherwise I think Meridian is expecting you to use their controller with Trinnov, Datasat, or Storm Audio. Is that the Meridian processor configuration you weren't able to get working?

@krams perhaps the Meridian HD 621 does not support the audio codecs you are using, from your HDMI source. It was introduced quite a long time ago. There is a newer Meridian UHD722 but I suspect you might need the Meridian 271 with one of the processors I mentioned earlier. Have you asked your Meridian dealer?