diff --git a/dlls/dsound/primary.c b/dlls/dsound/primary.c
index bf76dec2676..bc72d782b07 100644
--- a/dlls/dsound/primary.c
+++ b/dlls/dsound/primary.c
@@ -80,6 +80,7 @@ static HRESULT DSOUND_WaveFormat(DirectSoundDevice *device, IAudioClient *client
             mixwfe->Format.nChannels = 2;
             mixwfe->Format.nBlockAlign = mixwfe->Format.nChannels * mixwfe->Format.wBitsPerSample / 8;
             mixwfe->Format.nAvgBytesPerSec = mixwfe->Format.nSamplesPerSec * mixwfe->Format.nBlockAlign;
+            mixwfe->dwChannelMask = SPEAKER_FRONT_LEFT | SPEAKER_FRONT_RIGHT;
         }
 
         if (!IsEqualGUID(&mixwfe->SubFormat, &KSDATAFORMAT_SUBTYPE_IEEE_FLOAT)) {