- use the channel B for surround40 and 51.

src/conf/cards/CMI8738-MC6.conf

@@ -30,7 +30,30 @@ CMI8738-MC6.pcm.rear.0 {
 
 <confdir:pcm/surround40.conf>
 
-CMI8738-MC6.pcm.surround40.0 "cards.CMI8738-MC6.pcm.front.0"
+CMI8738-MC6.pcm.surround40.0 {
+	@args [ CARD ]
+	@args.CARD {
+		type string
+	}
+	type hooks
+	slave.pcm {
+		type hw
+		card $CARD
+		device 1
+	}
+	hooks.0 {
+		type ctl_elems
+		hook_args [
+			{
+				name "Four Channel Mode"
+				lock true
+				preserve true
+				value false
+			}
+		]
+	}
+}	
+
 
 <confdir:pcm/surround51.conf>