diff --git a/src/add-ons/media/media-add-ons/mixer/MixerCore.cpp b/src/add-ons/media/media-add-ons/mixer/MixerCore.cpp
index 7fa011a495..4cc565a5d0 100644
--- a/src/add-ons/media/media-add-ons/mixer/MixerCore.cpp
+++ b/src/add-ons/media/media-add-ons/mixer/MixerCore.cpp
@@ -278,6 +278,13 @@ MixerCore::EnableOutput(bool enabled)
 		StartMixThread();
 }
 
+uint32
+MixerCore::OutputChannelCount()
+{
+	return (fOutput) ? fOutput->GetOutputChannelCount() : 0;
+}
+
+
 bool
 MixerCore::Start()
 {
diff --git a/src/add-ons/media/media-add-ons/mixer/MixerInput.cpp b/src/add-ons/media/media-add-ons/mixer/MixerInput.cpp
index 619112b338..35a68bd039 100644
--- a/src/add-ons/media/media-add-ons/mixer/MixerInput.cpp
+++ b/src/add-ons/media/media-add-ons/mixer/MixerInput.cpp
@@ -287,13 +287,39 @@ MixerInput::UpdateChannelDesignations()
 
 	printf("UpdateChannelDesignations: enter\n");
 
-	if (fInputChannelCount == 1 && (GetChannelMask(0, fInputChannelMask) & (B_CHANNEL_LEFT | B_CHANNEL_RIGHT))) {
-		// a left or right channel get's output as stereo on both
-		fInputChannelInfo[0].designations = B_CHANNEL_LEFT | B_CHANNEL_RIGHT;
-	} else {
-		// everything else get's mapped 1:1
-		for (int i = 0; i < fInputChannelCount; i++)
-			fInputChannelInfo[i].designations = GetChannelMask(i, fInputChannelMask);
+	// first apply a 1:1 mapping
+	for (int i = 0; i < fInputChannelCount; i++)
+		fInputChannelInfo[i].designations = GetChannelMask(i, fInputChannelMask);
+	
+	// specialize this, depending on the available physical output channels
+	switch (fCore->OutputChannelCount()) {
+		case 0:
+		case 1:
+			break;
+			
+		case 2:
+			if (fInputChannelCount == 1 && (GetChannelMask(0, fInputChannelMask) & (B_CHANNEL_LEFT | B_CHANNEL_RIGHT))) {
+				fInputChannelInfo[0].designations = B_CHANNEL_LEFT | B_CHANNEL_RIGHT;
+			}
+			break;
+			
+		default:
+			if (fInputChannelCount == 1 && (GetChannelMask(0, fInputChannelMask) & (B_CHANNEL_LEFT | B_CHANNEL_RIGHT))) {
+				fInputChannelInfo[0].designations = B_CHANNEL_LEFT | B_CHANNEL_RIGHT | B_CHANNEL_REARLEFT | B_CHANNEL_REARRIGHT;
+			}
+			if (fInputChannelCount == 2 && (GetChannelMask(0, fInputChannelMask) & B_CHANNEL_LEFT)) {
+				fInputChannelInfo[0].designations = B_CHANNEL_LEFT | B_CHANNEL_REARLEFT;
+			}
+			if (fInputChannelCount == 2 && (GetChannelMask(0, fInputChannelMask) & B_CHANNEL_RIGHT)) {
+				fInputChannelInfo[0].designations = B_CHANNEL_RIGHT | B_CHANNEL_REARRIGHT;
+			}
+			if (fInputChannelCount == 2 && (GetChannelMask(1, fInputChannelMask) & B_CHANNEL_LEFT)) {
+				fInputChannelInfo[1].designations = B_CHANNEL_LEFT | B_CHANNEL_REARLEFT;
+			}
+			if (fInputChannelCount == 2 && (GetChannelMask(1, fInputChannelMask) & B_CHANNEL_RIGHT)) {
+				fInputChannelInfo[1].designations = B_CHANNEL_RIGHT | B_CHANNEL_REARRIGHT;
+			}
+			break;
 	}
 
 	for (int i = 0; i < fInputChannelCount; i++)
diff --git a/src/add-ons/media/media-add-ons/mixer/MixerOutput.cpp b/src/add-ons/media/media-add-ons/mixer/MixerOutput.cpp
index e3f39eed78..2e7bb1b05a 100644
--- a/src/add-ons/media/media-add-ons/mixer/MixerOutput.cpp
+++ b/src/add-ons/media/media-add-ons/mixer/MixerOutput.cpp
@@ -82,7 +82,118 @@ MixerOutput::UpdateOutputChannels()
 void
 MixerOutput::AssignDefaultSources()
 {
-	// XXX assign default sources
+	uint32 mask = fOutput.format.u.raw_audio.channel_mask;
+	uint32 count = fOutputChannelCount;
+	
+	// assign default sources for a few known setups,
+	// everything else is left unchanged (it already is 1:1)
+
+	if (count == 1 && mask & (B_CHANNEL_LEFT | B_CHANNEL_RIGHT)) {
+		// we have only one phycial output channel, and use it as a mix of
+		// left, right, rear-left, rear-right, center and sub
+		printf("AssignDefaultSources: 1 channel setup\n");
+		fOutputChannelInfo[0].source_count = 6;
+		fOutputChannelInfo[0].source_gain[0] = 1.0;
+		fOutputChannelInfo[0].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_LEFT);
+		fOutputChannelInfo[0].source_gain[1] = 1.0;
+		fOutputChannelInfo[0].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_RIGHT);
+		fOutputChannelInfo[0].source_gain[2] = 0.8;
+		fOutputChannelInfo[0].source_type[2] = ChannelMaskToChannelType(B_CHANNEL_REARLEFT);
+		fOutputChannelInfo[0].source_gain[3] = 0.8;
+		fOutputChannelInfo[0].source_type[3] = ChannelMaskToChannelType(B_CHANNEL_REARRIGHT);
+		fOutputChannelInfo[0].source_gain[4] = 0.7;
+		fOutputChannelInfo[0].source_type[4] = ChannelMaskToChannelType(B_CHANNEL_CENTER);
+		fOutputChannelInfo[0].source_gain[5] = 0.6;
+		fOutputChannelInfo[0].source_type[5] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+	} else if (count == 2 && mask == (B_CHANNEL_LEFT | B_CHANNEL_RIGHT)) {
+		// we have have two phycial output channels
+		printf("AssignDefaultSources: 2 channel setup\n");
+		// left channel:
+		fOutputChannelInfo[0].source_count = 4;
+		fOutputChannelInfo[0].source_gain[0] = 1.0;
+		fOutputChannelInfo[0].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_LEFT);
+		fOutputChannelInfo[0].source_gain[1] = 0.8;
+		fOutputChannelInfo[0].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_REARLEFT);
+		fOutputChannelInfo[0].source_gain[2] = 0.7;
+		fOutputChannelInfo[0].source_type[2] = ChannelMaskToChannelType(B_CHANNEL_CENTER);
+		fOutputChannelInfo[0].source_gain[3] = 0.6;
+		fOutputChannelInfo[0].source_type[3] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// right channel:
+		fOutputChannelInfo[1].source_count = 4;
+		fOutputChannelInfo[1].source_gain[0] = 1.0;
+		fOutputChannelInfo[1].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_RIGHT);
+		fOutputChannelInfo[1].source_gain[1] = 0.8;
+		fOutputChannelInfo[1].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_REARRIGHT);
+		fOutputChannelInfo[1].source_gain[2] = 0.7;
+		fOutputChannelInfo[1].source_type[2] = ChannelMaskToChannelType(B_CHANNEL_CENTER);
+		fOutputChannelInfo[1].source_gain[3] = 0.6;
+		fOutputChannelInfo[1].source_type[3] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+	} else if (count == 4 && mask == (B_CHANNEL_LEFT | B_CHANNEL_RIGHT | B_CHANNEL_REARLEFT | B_CHANNEL_REARRIGHT)) {
+		printf("AssignDefaultSources: 4 channel setup\n");
+		// left channel:
+		fOutputChannelInfo[0].source_count = 3;
+		fOutputChannelInfo[0].source_gain[0] = 1.0;
+		fOutputChannelInfo[0].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_LEFT);
+		fOutputChannelInfo[0].source_gain[1] = 0.7;
+		fOutputChannelInfo[0].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_CENTER);
+		fOutputChannelInfo[0].source_gain[2] = 0.6;
+		fOutputChannelInfo[0].source_type[2] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// right channel:
+		fOutputChannelInfo[1].source_count = 3;
+		fOutputChannelInfo[1].source_gain[0] = 1.0;
+		fOutputChannelInfo[1].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_RIGHT);
+		fOutputChannelInfo[1].source_gain[1] = 0.7;
+		fOutputChannelInfo[1].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_CENTER);
+		fOutputChannelInfo[1].source_gain[2] = 0.6;
+		fOutputChannelInfo[1].source_type[2] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// rear-left channel:
+		fOutputChannelInfo[2].source_count = 2;
+		fOutputChannelInfo[2].source_gain[0] = 1.0;
+		fOutputChannelInfo[2].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_REARLEFT);
+		fOutputChannelInfo[2].source_gain[1] = 0.6;
+		fOutputChannelInfo[2].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// rear-right channel:
+		fOutputChannelInfo[3].source_count = 2;
+		fOutputChannelInfo[3].source_gain[0] = 1.0;
+		fOutputChannelInfo[3].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_REARRIGHT);
+		fOutputChannelInfo[3].source_gain[1] = 0.6;
+		fOutputChannelInfo[3].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+	} else if (count == 5 && mask == (B_CHANNEL_LEFT | B_CHANNEL_RIGHT | B_CHANNEL_REARLEFT | B_CHANNEL_REARRIGHT | B_CHANNEL_CENTER)) {
+		printf("AssignDefaultSources: 5 channel setup\n");
+		// left channel:
+		fOutputChannelInfo[0].source_count = 2;
+		fOutputChannelInfo[0].source_gain[0] = 1.0;
+		fOutputChannelInfo[0].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_LEFT);
+		fOutputChannelInfo[0].source_gain[1] = 0.6;
+		fOutputChannelInfo[0].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// right channel:
+		fOutputChannelInfo[1].source_count = 2;
+		fOutputChannelInfo[1].source_gain[0] = 1.0;
+		fOutputChannelInfo[1].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_RIGHT);
+		fOutputChannelInfo[1].source_gain[1] = 0.6;
+		fOutputChannelInfo[1].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// rear-left channel:
+		fOutputChannelInfo[2].source_count = 2;
+		fOutputChannelInfo[2].source_gain[0] = 1.0;
+		fOutputChannelInfo[2].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_REARLEFT);
+		fOutputChannelInfo[2].source_gain[1] = 0.6;
+		fOutputChannelInfo[2].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// rear-right channel:
+		fOutputChannelInfo[3].source_count = 2;
+		fOutputChannelInfo[3].source_gain[0] = 1.0;
+		fOutputChannelInfo[3].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_REARRIGHT);
+		fOutputChannelInfo[3].source_gain[1] = 0.6;
+		fOutputChannelInfo[3].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+		// center channel:
+		fOutputChannelInfo[4].source_count = 2;
+		fOutputChannelInfo[4].source_gain[0] = 1.0;
+		fOutputChannelInfo[4].source_type[0] = ChannelMaskToChannelType(B_CHANNEL_CENTER);
+		fOutputChannelInfo[4].source_gain[1] = 0.5;
+		fOutputChannelInfo[4].source_type[1] = ChannelMaskToChannelType(B_CHANNEL_SUB);
+	} else {
+		printf("AssignDefaultSources: no default setup\n");
+	}
+
 	for (int i = 0; i < fOutputChannelCount; i++) {
 		for (int j = 0; j < fOutputChannelInfo[i].source_count; j++) {
 			printf("AssignDefaultSources: output channel %d, source %d: des 0x%08X (type %2d), gain %.3f\n", i, j, ChannelTypeToChannelMask(fOutputChannelInfo[i].source_type[j]), fOutputChannelInfo[i].source_type[j], fOutputChannelInfo[i].source_gain[j]);