Revert "Remove startup sound artefact"

This reverts commit d70232dcd8.

src/minidexed.cpp

@@ -1305,10 +1305,6 @@ void CMiniDexed::ProcessSound (void)
 	unsigned nFrames = m_nQueueSizeFrames - m_pSoundDevice->GetQueueFramesAvail ();
 	if (nFrames >= m_nQueueSizeFrames/2)
 	{
-		// only process the minimum number of frames (== chunksize / 2)
-		// as the tg_mixer cannot process more
-		nFrames = m_nQueueSizeFrames / 2;
-
 		if (m_bProfileEnabled)
 		{
 			m_GetChunkTimer.Start ();