Thank you for you info.
I'm particulary interesed in 2 channels output for "normal" and hi-res audio files, not for surround. I only have an external DAC and a stereo amplifier, I'm not using a receiver.
I have an important lossless music library (FLAC and WAV), almost 30% of it in hi-res audio formats (24-bit/96KHz, 24-bit/88.2KHz and 24-bit/192KHz). That's why is so important to me to find a solution to output audio files over optical digital (or coaxial digital) bit-perfect, with no resampling. That's why I've choosed Minix Neo U1 and LibreELEC (btw, thanks kszaq for doing this ).
I just wanted a single device who can handle all kind of media files and it was very difficult to find clear informations regarding this audio requirement and to find a suitable combination of hardware and software for my needs And, despite my efforts, I had a final surprise ...
Sorry for this small offtopic but maybe this info which came up (Amlogic does not support 24-bit/192KHz over S/DIF TOSlink) could be important for other users too.
As far as I'm aware this issue is not specifically related to just Amlogic, 24bit/48KHz was the original design spec for S/PDIF but as technology progressed higher bit rates where supported but both the sender and receiver have to support it. These boxes are cheap chinese devices hence I said don't expect miracles. I'm not 100% sure if these boxes are capable of a 24/192 stream, I think your best option is to build a media PC with a high end sound card, sorry I couldn't be of more help.