[PORTCLS]

- Use silence buffer when no audio buffers are available. Replaces the endless disturbing sound loop.
- Sound still broken

svn path=/trunk/; revision=45358

reactos/drivers/wdm/audio/backpln/portcls/irpstream.cpp

@@ -267,7 +267,6 @@ CIrpQueue::GetMapping(
     if (!Irp)
     {
         DPRINT("NoIrp\n");
-        return STATUS_UNSUCCESSFUL;
         // no irp available, use silence buffer
         *Buffer = (PUCHAR)m_SilenceBuffer;
         *BufferSize = m_MaxFrameSize;