[DSOUND] add DirectSoundFullDuplex support

[Marcus Meissner]

[I can the rest ... there is just one real point I need to make here.]

> I'm saying that from a newcomers fantastically objective POV, there
> might be a more efficient way than what everybody here's used to.  And
> I do appreciate that you take time to tell me why I'm wrong.  Thanks!

We work this way for quite some time and the speed of development was
only hindered by the number of developers involved and patches submitted
up to now.

It was never hindered by the number of patches applied.
 
Ciao, Marcus