5.1 upmix over HDMI for shairport and squeezelite

Hey, guys

Is it possible to upmix stereo to 5.1 over HDMI? In Kodi I’m able to do this and while testing Pi Musicbox I noticed their system featured this option.

I’ve done a bit of research into ALSA and found some info, specifically:

Then add the following to your ALSA configuration file of choice (either /etc/asound.conf or ~/.asoundrc):

pcm.upmix51 {
type upmix
slave.pcm „surround51“
delay 15
channels 6
}

But this doesn’t help. Any suggestions?