xenobioz wrote:Maybe the wave out driver for buzz needs to updated.
having recently written a wasapi driver, yes, the one in buzz is not ideal and doesn't handle all the corner cases correctly. for example it frequently defaults to 16bit when 32bit would actually be possible / correct. i suspect your distortion is a bitrate conversion issue actually (i think the buzz driver doesn't support 32bit int at all, or was it float, can't remember, but there's no reason not to). i also remember some issue with distortion in 32bit (or 24bit not sure anymore) output where the output level was slightly too high after (seemingly correct) clamping which i had to take care of. they also worked around this issue in the psycle wasapi driver btw.
another thing that could go wrong is the channel count (it shows 8 in your case, and i specifically had to handle cases > 2 in my code to get it to route to the right channels and interleave correctly), not sure if this is handled correctly in the buzz driver now.
one problem that has no workaround sadly: in shared mode on my RME, if the buffersize in wasapi is bigger than what i set in the device settings for my RME audio driver, i get completely garbled output. the only fix is to adjust the WDM buffer size in the RME control panel, wasapi doesn't expose any api to do this (unlike ASIO for example). this leads to the absurd situation that on professional cards, wasapi is actually less "integrated" than on onboard stuff (where there simply are no such settings and the defaults magically work). so, if getbuffersize reports for example 512, then try to set your card's buffers size to that too, or just try different sizes... however if shared mode works well in other apps, most likely this is not the issue, but the buzz driver is at fault.
(no wonder, implementing wasapi is far messier than i expected from a new and generally pretty good api, i needed to test on lots of different hardware to get out all the kinks... the problems stem more from the underlying hardware drivers and lack of integration with the device driver than wasapi itself).