diff --git a/dlls/dsound/primary.c b/dlls/dsound/primary.c
index 0bfd56671cd..a8244777f8e 100644
--- a/dlls/dsound/primary.c
+++ b/dlls/dsound/primary.c
@@ -440,35 +440,24 @@ HRESULT DSOUND_PrimaryGetPosition(DirectSoundDevice *device, LPDWORD playpos, LP
 	return DS_OK;
 }
 
-static DWORD DSOUND_GetFormatSize(LPCWAVEFORMATEX wfex)
+WAVEFORMATEX *DSOUND_CopyFormat(const WAVEFORMATEX *wfex)
 {
-	if (wfex->wFormatTag == WAVE_FORMAT_PCM)
-		return sizeof(WAVEFORMATEX);
-	else
-		return sizeof(WAVEFORMATEX) + wfex->cbSize;
-}
+    WAVEFORMATEX *pwfx;
+    if(wfex->wFormatTag == WAVE_FORMAT_PCM){
+        pwfx = HeapAlloc(GetProcessHeap(), 0, sizeof(WAVEFORMATEX));
+        CopyMemory(pwfx, wfex, sizeof(PCMWAVEFORMAT));
+        pwfx->cbSize = 0;
+    }else{
+        pwfx = HeapAlloc(GetProcessHeap(), 0, sizeof(WAVEFORMATEX) + wfex->cbSize);
+        CopyMemory(pwfx, wfex, sizeof(WAVEFORMATEX) + wfex->cbSize);
+    }
 
-LPWAVEFORMATEX DSOUND_CopyFormat(LPCWAVEFORMATEX wfex)
-{
-	DWORD size = DSOUND_GetFormatSize(wfex);
-	LPWAVEFORMATEX pwfx = HeapAlloc(GetProcessHeap(),0,size);
-	if (pwfx == NULL) {
-		WARN("out of memory\n");
-	} else if (wfex->wFormatTag != WAVE_FORMAT_PCM) {
-		CopyMemory(pwfx, wfex, size);
-	} else {
-		CopyMemory(pwfx, wfex, sizeof(PCMWAVEFORMAT));
-		pwfx->cbSize=0;
-		if (pwfx->nBlockAlign != pwfx->nChannels * pwfx->wBitsPerSample/8) {
-			WARN("Fixing bad nBlockAlign (%u)\n", pwfx->nBlockAlign);
-			pwfx->nBlockAlign  = pwfx->nChannels * pwfx->wBitsPerSample/8;
-		}
-		if (pwfx->nAvgBytesPerSec != pwfx->nSamplesPerSec * pwfx->nBlockAlign) {
-			WARN("Fixing bad nAvgBytesPerSec (%u)\n", pwfx->nAvgBytesPerSec);
-			pwfx->nAvgBytesPerSec  = pwfx->nSamplesPerSec * pwfx->nBlockAlign;
-		}
-	}
-	return pwfx;
+    if(pwfx->wFormatTag == WAVE_FORMAT_PCM ||
+            (pwfx->wFormatTag == WAVE_FORMAT_EXTENSIBLE &&
+             IsEqualGUID(&((const WAVEFORMATEXTENSIBLE*)pwfx)->SubFormat, &KSDATAFORMAT_SUBTYPE_PCM)))
+        pwfx->nBlockAlign = (pwfx->nChannels * pwfx->wBitsPerSample) / 8;
+
+    return pwfx;
 }
 
 HRESULT primarybuffer_SetFormat(DirectSoundDevice *device, LPCWAVEFORMATEX passed_fmt)
@@ -545,27 +534,9 @@ done:
 			device->primary_pwfx = old_fmt;
 		else
 			HeapFree(GetProcessHeap(), 0, old_fmt);
-	} else if (passed_fmt->wFormatTag == WAVE_FORMAT_PCM ||
-		   passed_fmt->wFormatTag == WAVE_FORMAT_IEEE_FLOAT) {
-		/* Fill in "real" values to primary_pwfx */
-		WAVEFORMATEX *fmt = device->primary_pwfx;
-
-		*fmt = *device->pwfx;
-		fmtex = (void*)device->pwfx;
-
-		if (IsEqualGUID(&fmtex->SubFormat, &KSDATAFORMAT_SUBTYPE_IEEE_FLOAT) &&
-		    passed_fmt->wFormatTag == WAVE_FORMAT_IEEE_FLOAT) {
-			fmt->wFormatTag = WAVE_FORMAT_IEEE_FLOAT;
-		} else {
-			fmt->wFormatTag = WAVE_FORMAT_PCM;
-			fmt->wBitsPerSample = 16;
-		}
-		fmt->nBlockAlign = fmt->nChannels * fmt->wBitsPerSample / 8;
-		fmt->nAvgBytesPerSec = fmt->nBlockAlign * fmt->nSamplesPerSec;
-		fmt->cbSize = 0;
 	} else {
-		device->primary_pwfx = HeapReAlloc(GetProcessHeap(), 0, device->primary_pwfx, sizeof(*fmtex));
-		memcpy(device->primary_pwfx, device->pwfx, sizeof(*fmtex));
+		HeapFree(GetProcessHeap(), 0, device->primary_pwfx);
+		device->primary_pwfx = DSOUND_CopyFormat(passed_fmt);
 	}
 
 out:
diff --git a/dlls/dsound/tests/dsound.c b/dlls/dsound/tests/dsound.c
index 4291e7a114d..bca0d76267f 100644
--- a/dlls/dsound/tests/dsound.c
+++ b/dlls/dsound/tests/dsound.c
@@ -1348,6 +1348,15 @@ static HRESULT test_invalid_fmts(LPGUID lpGuid)
         rc = IDirectSoundBuffer_SetFormat(primary, &wfx);
         ok(rc == S_OK, "SetFormat: %08x\n", rc);
 
+        rc = IDirectSoundBuffer_GetFormat(primary, &wfx, sizeof(wfx), NULL);
+        ok(rc == S_OK, "GetFormat: %08x\n", rc);
+        ok(wfx.wFormatTag == WAVE_FORMAT_PCM, "format: 0x%x\n", wfx.wFormatTag);
+        ok(wfx.nChannels == 2, "channels: %u\n", wfx.nChannels);
+        ok(wfx.nSamplesPerSec == 44100, "rate: %u\n", wfx.nSamplesPerSec);
+        ok(wfx.wBitsPerSample == 16, "bps: %u\n", wfx.wBitsPerSample);
+        ok(wfx.nBlockAlign == 4, "blockalign: %u\n", wfx.nBlockAlign);
+        ok(wfx.nAvgBytesPerSec == 44100 * 4 + 1, "avgbytes: %u\n", wfx.nAvgBytesPerSec);
+
         wfx.nChannels = 2;
         wfx.nSamplesPerSec = 44100;
         wfx.wBitsPerSample = 16;
@@ -1356,6 +1365,15 @@ static HRESULT test_invalid_fmts(LPGUID lpGuid)
         rc = IDirectSoundBuffer_SetFormat(primary, &wfx);
         ok(rc == S_OK, "SetFormat: %08x\n", rc);
 
+        rc = IDirectSoundBuffer_GetFormat(primary, &wfx, sizeof(wfx), NULL);
+        ok(rc == S_OK, "GetFormat: %08x\n", rc);
+        ok(wfx.wFormatTag == WAVE_FORMAT_PCM, "format: 0x%x\n", wfx.wFormatTag);
+        ok(wfx.nChannels == 2, "channels: %u\n", wfx.nChannels);
+        ok(wfx.nSamplesPerSec == 44100, "rate: %u\n", wfx.nSamplesPerSec);
+        ok(wfx.wBitsPerSample == 16, "bps: %u\n", wfx.wBitsPerSample);
+        ok(wfx.nBlockAlign == 4, "blockalign: %u\n", wfx.nBlockAlign);
+        ok(wfx.nAvgBytesPerSec == 44100 * 4 - 1, "avgbytes: %u\n", wfx.nAvgBytesPerSec);
+
         wfx.nChannels = 2;
         wfx.nSamplesPerSec = 44100;
         wfx.wBitsPerSample = 16;
@@ -1364,6 +1382,33 @@ static HRESULT test_invalid_fmts(LPGUID lpGuid)
         rc = IDirectSoundBuffer_SetFormat(primary, &wfx);
         ok(rc == S_OK, "SetFormat: %08x\n", rc);
 
+        rc = IDirectSoundBuffer_GetFormat(primary, &wfx, sizeof(wfx), NULL);
+        ok(rc == S_OK, "GetFormat: %08x\n", rc);
+        ok(wfx.wFormatTag == WAVE_FORMAT_PCM, "format: 0x%x\n", wfx.wFormatTag);
+        ok(wfx.nChannels == 2, "channels: %u\n", wfx.nChannels);
+        ok(wfx.nSamplesPerSec == 44100, "rate: %u\n", wfx.nSamplesPerSec);
+        ok(wfx.wBitsPerSample == 16, "bps: %u\n", wfx.wBitsPerSample);
+        ok(wfx.nBlockAlign == 4, "blockalign: %u\n", wfx.nBlockAlign);
+        ok(wfx.nAvgBytesPerSec == 44100 * 4 + 1, "avgbytes: %u\n", wfx.nAvgBytesPerSec);
+
+        wfx.wFormatTag = WAVE_FORMAT_ALAW;
+        wfx.nChannels = 2;
+        wfx.nSamplesPerSec = 44100;
+        wfx.wBitsPerSample = 16;
+        wfx.nBlockAlign = wfx.nChannels * wfx.wBitsPerSample / 8;
+        wfx.nAvgBytesPerSec = wfx.nSamplesPerSec * wfx.nBlockAlign;
+        rc = IDirectSoundBuffer_SetFormat(primary, &wfx);
+        ok(rc == S_OK, "SetFormat: %08x\n", rc);
+
+        rc = IDirectSoundBuffer_GetFormat(primary, &wfx, sizeof(wfx), NULL);
+        ok(rc == S_OK, "GetFormat: %08x\n", rc);
+        ok(wfx.wFormatTag == WAVE_FORMAT_ALAW, "format: 0x%x\n", wfx.wFormatTag);
+        ok(wfx.nChannels == 2, "channels: %u\n", wfx.nChannels);
+        ok(wfx.nSamplesPerSec == 44100, "rate: %u\n", wfx.nSamplesPerSec);
+        ok(wfx.wBitsPerSample == 16, "bps: %u\n", wfx.wBitsPerSample);
+        ok(wfx.nBlockAlign == 4, "blockalign: %u\n", wfx.nBlockAlign);
+        ok(wfx.nAvgBytesPerSec == 44100 * 4, "avgbytes: %u\n", wfx.nAvgBytesPerSec);
+
         fmtex.Format.cbSize = sizeof(WAVEFORMATEXTENSIBLE) - sizeof(WAVEFORMATEX);
         fmtex.Format.wFormatTag = WAVE_FORMAT_EXTENSIBLE;
         fmtex.Format.nChannels = 2;
@@ -1377,6 +1422,19 @@ static HRESULT test_invalid_fmts(LPGUID lpGuid)
         rc = IDirectSoundBuffer_SetFormat(primary, (WAVEFORMATEX*)&fmtex);
         ok(rc == S_OK, "SetFormat: %08x\n", rc);
 
+        rc = IDirectSoundBuffer_GetFormat(primary, (WAVEFORMATEX*)&fmtex, sizeof(fmtex), NULL);
+        ok(rc == S_OK, "GetFormat: %08x\n", rc);
+        ok(fmtex.Format.wFormatTag == WAVE_FORMAT_EXTENSIBLE, "format: 0x%x\n", fmtex.Format.wFormatTag);
+        ok(fmtex.Format.nChannels == 2, "channels: %u\n", fmtex.Format.nChannels);
+        ok(fmtex.Format.nSamplesPerSec == 44100, "rate: %u\n", fmtex.Format.nSamplesPerSec);
+        ok(fmtex.Format.wBitsPerSample == 16, "bps: %u\n", fmtex.Format.wBitsPerSample);
+        ok(fmtex.Format.nBlockAlign == 4, "blockalign: %u\n", fmtex.Format.nBlockAlign);
+        ok(fmtex.Format.nAvgBytesPerSec == 44100 * 4, "avgbytes: %u\n", fmtex.Format.nAvgBytesPerSec);
+        ok(fmtex.Samples.wValidBitsPerSample == 0 || /* <= XP */
+                fmtex.Samples.wValidBitsPerSample == 16, /* >= Vista */
+                "validbits: %u\n", fmtex.Samples.wValidBitsPerSample);
+        ok(IsEqualGUID(&fmtex.SubFormat, &KSDATAFORMAT_SUBTYPE_PCM), "subtype incorrect\n");
+
         fmtex.Format.cbSize = sizeof(WAVEFORMATEXTENSIBLE) - sizeof(WAVEFORMATEX);
         fmtex.Format.wFormatTag = WAVE_FORMAT_EXTENSIBLE;
         fmtex.Format.nChannels = 2;
@@ -1390,6 +1448,17 @@ static HRESULT test_invalid_fmts(LPGUID lpGuid)
         rc = IDirectSoundBuffer_SetFormat(primary, (WAVEFORMATEX*)&fmtex);
         ok(rc == S_OK, "SetFormat: %08x\n", rc);
 
+        rc = IDirectSoundBuffer_GetFormat(primary, (WAVEFORMATEX*)&fmtex, sizeof(fmtex), NULL);
+        ok(rc == S_OK, "GetFormat: %08x\n", rc);
+        ok(fmtex.Format.wFormatTag == WAVE_FORMAT_EXTENSIBLE, "format: 0x%x\n", fmtex.Format.wFormatTag);
+        ok(fmtex.Format.nChannels == 2, "channels: %u\n", fmtex.Format.nChannels);
+        ok(fmtex.Format.nSamplesPerSec == 44100, "rate: %u\n", fmtex.Format.nSamplesPerSec);
+        ok(fmtex.Format.wBitsPerSample == 24, "bps: %u\n", fmtex.Format.wBitsPerSample);
+        ok(fmtex.Format.nBlockAlign == 6, "blockalign: %u\n", fmtex.Format.nBlockAlign);
+        ok(fmtex.Format.nAvgBytesPerSec == 44100 * 6, "avgbytes: %u\n", fmtex.Format.nAvgBytesPerSec);
+        ok(fmtex.Samples.wValidBitsPerSample == 20, "validbits: %u\n", fmtex.Samples.wValidBitsPerSample);
+        ok(IsEqualGUID(&fmtex.SubFormat, &KSDATAFORMAT_SUBTYPE_PCM), "subtype incorrect\n");
+
         fmtex.Format.cbSize = sizeof(WAVEFORMATEXTENSIBLE) - sizeof(WAVEFORMATEX);
         fmtex.Format.wFormatTag = WAVE_FORMAT_EXTENSIBLE;
         fmtex.Format.nChannels = 2;