diff --git a/dlls/winepulse.drv/mmdevdrv.c b/dlls/winepulse.drv/mmdevdrv.c
index 7e2877f184e..b85d9b5e80b 100644
--- a/dlls/winepulse.drv/mmdevdrv.c
+++ b/dlls/winepulse.drv/mmdevdrv.c
@@ -1222,28 +1222,10 @@ static HRESULT WINAPI AudioCaptureClient_ReleaseBuffer(
 
     TRACE("(%p)->(%u)\n", This, done);
 
-    pulse->lock();
-    if (!This->pulse_stream->locked && done) {
-        pulse->unlock();
-        return AUDCLNT_E_OUT_OF_ORDER;
-    }
-    if (done && This->pulse_stream->locked != done) {
-        pulse->unlock();
-        return AUDCLNT_E_INVALID_SIZE;
-    }
-    if (done) {
-        ACPacket *packet = This->pulse_stream->locked_ptr;
-        This->pulse_stream->locked_ptr = NULL;
-        This->pulse_stream->held_bytes -= This->pulse_stream->period_bytes;
-        if (packet->discont)
-            This->pulse_stream->clock_written += 2 * This->pulse_stream->period_bytes;
-        else
-            This->pulse_stream->clock_written += This->pulse_stream->period_bytes;
-        list_add_tail(&This->pulse_stream->packet_free_head, &packet->entry);
-    }
-    This->pulse_stream->locked = 0;
-    pulse->unlock();
-    return S_OK;
+    if (!This->pulse_stream)
+        return AUDCLNT_E_NOT_INITIALIZED;
+
+    return pulse->release_capture_buffer(This->pulse_stream, done);
 }
 
 static HRESULT WINAPI AudioCaptureClient_GetNextPacketSize(
diff --git a/dlls/winepulse.drv/pulse.c b/dlls/winepulse.drv/pulse.c
index 15173647836..4ff3753c189 100644
--- a/dlls/winepulse.drv/pulse.c
+++ b/dlls/winepulse.drv/pulse.c
@@ -1591,6 +1591,35 @@ static HRESULT WINAPI pulse_get_capture_buffer(struct pulse_stream *stream, BYTE
     return *frames ? S_OK : AUDCLNT_S_BUFFER_EMPTY;
 }
 
+static HRESULT WINAPI pulse_release_capture_buffer(struct pulse_stream *stream, BOOL done)
+{
+    pulse_lock();
+    if (!stream->locked && done)
+    {
+        pulse_unlock();
+        return AUDCLNT_E_OUT_OF_ORDER;
+    }
+    if (done && stream->locked != done)
+    {
+        pulse_unlock();
+        return AUDCLNT_E_INVALID_SIZE;
+    }
+    if (done)
+    {
+        ACPacket *packet = stream->locked_ptr;
+        stream->locked_ptr = NULL;
+        stream->held_bytes -= stream->period_bytes;
+        if (packet->discont)
+            stream->clock_written += 2 * stream->period_bytes;
+        else
+            stream->clock_written += stream->period_bytes;
+        list_add_tail(&stream->packet_free_head, &packet->entry);
+    }
+    stream->locked = 0;
+    pulse_unlock();
+    return S_OK;
+}
+
 static HRESULT WINAPI pulse_get_buffer_size(struct pulse_stream *stream, UINT32 *out)
 {
     HRESULT hr = S_OK;
@@ -1687,6 +1716,7 @@ static const struct unix_funcs unix_funcs =
     pulse_get_render_buffer,
     pulse_release_render_buffer,
     pulse_get_capture_buffer,
+    pulse_release_capture_buffer,
     pulse_get_buffer_size,
     pulse_get_latency,
     pulse_get_current_padding,
diff --git a/dlls/winepulse.drv/unixlib.h b/dlls/winepulse.drv/unixlib.h
index ad6dd2da1f5..e3471607d26 100644
--- a/dlls/winepulse.drv/unixlib.h
+++ b/dlls/winepulse.drv/unixlib.h
@@ -86,6 +86,7 @@ struct unix_funcs
                                             DWORD flags);
     HRESULT (WINAPI *get_capture_buffer)(struct pulse_stream *stream, BYTE **data, UINT32 *frames,
                                          DWORD *flags, UINT64 *devpos, UINT64 *qpcpos);
+    HRESULT (WINAPI *release_capture_buffer)(struct pulse_stream *stream, BOOL done);
     HRESULT (WINAPI *get_buffer_size)(struct pulse_stream *stream, UINT32 *out);
     HRESULT (WINAPI *get_latency)(struct pulse_stream *stream, REFERENCE_TIME *latency);
     HRESULT (WINAPI *get_current_padding)(struct pulse_stream *stream, UINT32 *out);