About Surround Sound

Hello!
So my soon to be wife and I are going to be dedicating one of the rooms in our house to gaming and with this I will be installing a slightly older (about 2011 or so) 5.1 surround sound AVR to really pull my players in. This AVR can use HDMI or decode DTS/Dolby Digital across an optical toslink cable.
Using the optical input will make this entire endeavor much simpler and I was wondering if you guys know if Syrinscape can output in a format that can be sent via toslink and then decoded by my AVR. Is Syrinscape outputting raw multi-channel surround and necessitate the use of HDMI?
Any help is appreciated as I’ll be getting all the equipment and cabling required for the job soon.
Thanks!