flac 5.1 read as stereo

[ibasaw]

hi

Server
10.10.7
Version web
10.10.7 (f4b8aa0ed4)
build Release

player desktop on windows 10

i can play dolby atmos and dts hd-ma on my AVR receiver => 7.2.4 channels
i try to listen music flac as 5.1 channels, the player play only stereo => AVR show only stereo

Here the audio specifications
Audio
Titre: FLAC - 5.1
Codec: FLAC
AVC: No
Agencement: 5.1
Chaînes: 6 ch
Débit: 1582 kbps
Taux d’échantillonnage: 48000 Hz
Profondeur de bit: 24 bit
Par défaut: No
Forcé: No
Externe: No

why i cant read it as 5.1 ?

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