Things to check:
Mi Box:
In Settings > Sound and Display > Digital Sound > {set to HDMI}. It might be on PCM
On Kodi:
Goto Settings > System Information > Audio > Allow Passthrough
On your Receiver:
Set HDMI to "Bitstream" if it's audio is set to PCM.
Thanks for responding sci-fi fan.
I got my Mibox 3 from Globe and installed Kodi ver 17.6. I have re-checked my Mibox and kodi settings but still unable to play DTS. The weird part is that Kodi detects the dts track when I click "info" but my receiver does not detect the multi-channel stream. However, if I play a movie with Dolby Digital 5.1, my receiver can detect it. My receiver is a Marantz SR5007. Without changing any setting, I tried using VLC and was able to play both DTS and Dolby Digital multichannel tracks.
Also, I have an old unbranded android box running android 4.4 and Kodi 15.4 which is able to play both DTS and Dolby Digital as detected by my receiver. Problem is the audio does not sync and there is a lot of stutter making it unwatchable. I bought the Mibox 3 hoping it will do the job.
Any more suggestions will be appreciated.