Bug Video player component downmixes surround sound to stereo in 2018.4.30f1

Unity recognizes the video file as having 6 channels in inspector, but appears to downmix it to stereo and output to all speakers during runtime.

I feel like in an earlier version of 2018.4 surround sound was working in video player, but does not seem to be anymore (I may be mistaken).

Tried in both Audio Source and Direct output modes, both with same result. Surround sound in engine otherwise works outside the video player (ie, moving around in 3D gameplay). Video is not set to be transcoded.

Test file - I'm attaching a test video file that exhibits the problem. In the test file, footsteps should not be audible in surround (only music). If you open with VLC, it plays correctly (no footsteps in rear speakers). In Unity, footsteps can be heard in rear speakers.

 

Did you ever find a fix for this?

 

Yes, this appears to be the case and is driving me a bit nuts at the moment. Was investigating this as a bug in AVPro but even just dragging in an mp4, it downmixes. All help appreciated.