How do I select a specific audio device for a file? ex: 5.1

[hyeguy123]

I recently downloaded an movie in mp4 format that bsplayer v 2.33 automatically defaults to playing in 5.1 surround sound audio (which my computer can't play) resulting in only barely audible whispers (I can very much hear the loud explosions and car crashes in the movie though).

What is a setting in bsplayer v 2.33 that I can change to go from the defaulted 5.1 surround sound track to a stereo track? (I know this file is capable of doing it because I have tried it in other media players).

Also, when I right click and go to audio streams, there is only one option (GPAC ISO Audio Handler [Undetermined] )

Also, when I right click and go to preferences, then audio, there is only one default audio stream available. But, when I click to choose stereo in InterVideo AC3, the setting never gets applied.