Buzz TV XRS 4500 - stereo only?

I have a Buzz TV XRS4500 connected to a Denon X3400H receiver which supports ATMOS. I have a 5.1.2 setup. When I look at the source info from the BuzztV it alwas shows up as stereo only. No matter what I play. Even If i play a local file/movie which is either 5/1. 7.1 or ATMOS - the input to the receiver always states stereo and then my stereo upmixes this to ATMOS.
Does this box not support multichannel audio natively?

c and p

Majority of streams from IPTV are in 2.0 Audio
If you have a stream that is broadcast in Dolby or DTS, the Buzz app is capable of streaming it using Software Decoding through FFMPEG.

Understood about the streams. What about local files though? Am I missing something in the settings? I tried everything, but still seems to be outputting only in stereo. I used VLC as the player for local files.