Maybe I forgot to explain. My test application was run with WINEDLLOVERRIDES=quartz=n in order to use the native quartz.dll . With this, audio does not stutter. The explanation about the DirectDraw implementation in Wine being based on top of GDI does not explain how native quartz manages to play smoothly while builtin quartz stutters *when both are run under Wine*.
Yes, I understood that part in your first mail. My point was that while the implementation of native quartz MAY be more efficient, using DirectDraw in Wine is not faster than using GDI directly per se. That doesn't mean that native can't be faster than builtin, but that would be because of a better implementation, not because it uses 2D ddraw. Direct3D, on the other hand, would be hw accelerated, and thus faster. Sorry that I didn't make this clear.