[Bug 29274] New: Steam on Mac - mic test fails and crashes Counter Strike 1.6

http://bugs.winehq.org/show_bug.cgi?id=29274

Bug #: 29274
           Summary: Steam on Mac - mic test fails and crashes Counter
                    Strike 1.6
           Product: Wine
           Version: 1.3.34
          Platform: x86-64
        OS/Version: Mac OS X
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]
    Classification: Unclassified

Created attachment 37861
  --> http://bugs.winehq.org/attachment.cgi?id=37861
Winedebug dump with +coreaudio

When starting Counter Strike 1.6 game crashes or shows error messages and then
continues without sound.
Similar thing happens if you click "Test microphone" in Steam Settings>Voice.
Attaching debug of coreaudio.

Found one solution, but not sure it is proper one:

Appears that 
in dlls/winecoreaudio/mmdevdrv.c
in AudioCaptureClient_ReleaseBuffer function

This->public_buffer is sometimes empty and makes this crash.

So, changed:

pbuf_frames = This->public_buffer->mAudioDataByteSize / This->fmt->nBlockAlign;

to:

if (This->public_buffer)
    pbuf_frames = This->public_buffer->mAudioDataByteSize /
This->fmt->nBlockAlign;

Programmer myself, but don't have time to explore where real error is. This fix
makes game work without crash, but think problem is where is
This->public_buffer released (or not set...)