Playback of 5.1 audio track

[shinigamidaiko]

Hello, I'm trying to playback a surround audio track sent from my PC (using MPC classic with LAV audio as a decoder) to a soundbar (Sony HT-ZF9). The English track which you see below plays perfectly in surround, but not the Japanese one (Flac 5.1).

I tried playing it through my Apple TV 4K and the surround works fine for the Japanese 5.1 Flac track. Any idea what I need to do to reproduce the same playback behavior on my PC? Thank you for any suggestions?

Audio #1
ID : 2
Format : FLAC
Format/Info : Free Lossless Audio Codec
Codec ID : A_FLAC
Duration : 2 h 13 min
Bit rate mode : Variable
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Bit depth : 16 bits
Compression mode : Lossless
Title : FLAC 5.1
Writing library : libFLAC 1.2.1 (UTC 2007-09-17)
Language : Japanese
Default : Yes
Forced : No

Audio #2
ID : 3
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Codec ID : A_AC3
Duration : 2 h 13 min
Bit rate mode : Constant
Bit rate : 448 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Stream size : 427 MiB (2%)
Title : AC3 5.1
Language : English
Service kind : Complete Main
Default : No
Forced : No

[shinigamidaiko]

Can anyone offer their advice regarding this issue?

[johns0]

Encode the flac to ac3.