You can buy a toslink adapter locally, about R30. I could never get Netflix DD or DTS to work via the optical out. Pass through via HDMI works fine but my AV receiver supports all the latest formats, including DD+.
KODI 5.1 HDMI pass through and optical via the Toslink optical port work...
Netflix 5.1 support
Netflix 5.1 works via HDMI if your receiving device supports DD+
Netflix 5.1 does not work via the optical out
I successfully used a cheap HDMI Switch which strips the audio from HDMI and put that out optically to obtain Netflix 5.1 via optical
Note there is an built-in...