Audio muted when tabbing out regardless of system setting

[xpdota]

My audio crashed, so I installed the plugin. The "Reset Audio Now" button didn't work, so I hit "Try Harder" instead. It worked, but sound was muted when I tabbed out.

Repro:

1. Turn on the "Play sounds when window is not active" setting in the normal game System Configuration
2. Click "Try Harder"
3. Tab out. Sound is muted.
4. To fix, I had to uncheck the "Play sounds when window is not active" option, check it again, and then apply.