diff --git a/src/hardware/sblaster.cpp b/src/hardware/sblaster.cpp
index 875c75c8..d5da7e52 100644
--- a/src/hardware/sblaster.cpp
+++ b/src/hardware/sblaster.cpp
@@ -758,6 +758,16 @@ static void DSP_ADC_CallBack(DmaChannel * /*chan*/, DMAEvent event) {
 	ch->Register_Callback(0);
 }
 
+static void DSP_ChangeRate(Bitu freq) {
+	if (sb.freq!=freq && sb.dma.mode!=DSP_DMA_NONE) {
+		sb.chan->FillUp();
+		sb.chan->SetFreq(freq / (sb.mixer.stereo ? 2 : 1));
+		sb.dma.rate=(freq*sb.dma.mul) >> SB_SH;
+		sb.dma.min=(sb.dma.rate*3)/1000;
+	}
+	sb.freq=freq;
+}
+
 Bitu DEBUG_EnableDebugger(void);
 
 #define DSP_SB16_ONLY if (sb.type != SBT_16) { LOG(LOG_SB,LOG_ERROR)("DSP:Command %2X requires SB16",sb.dsp.cmd); break; }
@@ -845,16 +855,14 @@ static void DSP_DoCommand(void) {
 		if (sb.midi == true) MIDI_RawOutByte(sb.dsp.in.data[0]);
 		break;
 	case 0x40:	/* Set Timeconstant */
-		sb.freq=(1000000 / (256 - sb.dsp.in.data[0]));
-		/* Nasty kind of hack to allow runtime changing of frequency */
-		if (sb.dma.mode != DSP_DMA_NONE && sb.dma.autoinit) {
-			DSP_PrepareDMA_Old(sb.dma.mode,sb.dma.autoinit,sb.dma.sign);
-		}
+		DSP_ChangeRate(1000000 / (256 - sb.dsp.in.data[0]));
 		break;
 	case 0x41:	/* Set Output Samplerate */
-	case 0x42:	/* Set Input Samplerate */
 		DSP_SB16_ONLY;
-		sb.freq=(sb.dsp.in.data[0] << 8)  | sb.dsp.in.data[1];
+		DSP_ChangeRate((sb.dsp.in.data[0] << 8) | sb.dsp.in.data[1]);
+		break;
+	case 0x42:	/* Set Input Samplerate */
+		LOG(LOG_SB,LOG_ERROR)("DSP:Unimplemented input sample rate command");
 		break;
 	case 0x48:	/* Set DMA Block Size */
 		DSP_SB2_ABOVE;