Curiosity

I just installed Nightly (R.4d34280), I can not hear the audio.
I browsed directory (MuseScoreNightly/sound) and resolved. Perhaps it would be preferable that was already set. If I'm not mistaken version 75d780c.7z had by default.
I found a mine of midi files (Bach / Haydn) and open some of them.
Between version 1.2 and Nightly there are many differences.
Just dragging and dropping the files show up as in the image.
I can attach examples if useful, Franz