Just a quick check for me, if you wouldn't mind. ^_^
Can you right-click on the computer speaker icon in your bottom right area of the screen?
In the pop-up, click on "Playback devices".
Look for a green round checkbox icon in the list of devices (may very well be just 'Speakers'), and click on it.
Now click on the button in the lower left of this window named "Configure".
In the new window, check to make sure the area named 'Audio channels' has just "Stereo" selected, and select 'Next'.
De-check any checkboxes in the next window, if there are any selected, then click 'Next', then 'Finish'.
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Try the game again at this point, if it still doesn't have audio for Aoba, then may I ask for you to post a screenshot of the folder where DMMd is installed? It should look something like mine:
Attachment 166186
Pay attention to the file sizes, and look for the file specifically named "sound.npa".