After sound card detect test - sound works - why

[Richard Emberson]

So I start X.
I start xmms - its playing but there is no sound.
I then run the sound card detector (System Setting -> Soundcard Detection).
I click on "Play test sound" and volia, there is sound ... both the test
sound and what I am playing on xmms.
After the test sound stops, I clickon "Yes" I heard the sound and quit.

So, what does the "Play test sound" do and how can I have it happen
automatically.

Thanks.

Richard