Index: src/sys/dev/sound/pcm/ac97.c
===================================================================
RCS file: /home/ncvs/src/sys/dev/sound/pcm/ac97.c,v
retrieving revision 1.53.2.3
diff -u -r1.53.2.3 ac97.c
--- src/sys/dev/sound/pcm/ac97.c	9 Jan 2006 02:06:42 -0000	1.53.2.3
+++ src/sys/dev/sound/pcm/ac97.c	19 Apr 2007 04:25:03 -0000
@@ -28,6 +28,8 @@
 #include <dev/sound/pcm/ac97.h>
 #include <dev/sound/pcm/ac97_patch.h>
 
+#include <dev/pci/pcivar.h>
+
 #include "mixer_if.h"
 
 SND_DECLARE_FILE("$FreeBSD: src/sys/dev/sound/pcm/ac97.c,v 1.53.2.3 2006/01/09 02:06:42 ariff Exp $");
@@ -52,6 +54,7 @@
 	device_t dev;
 	void *devinfo;
 	u_int32_t id;
+	u_int32_t subvendor;
 	unsigned count, caps, se, extcaps, extid, extstat, noext:1;
 	u_int32_t flags;
 	struct ac97mixtable_entry mix[32];
@@ -150,7 +153,7 @@
 	{ 0x414c4740, 0x0f, 0, "ALC202", 	0 },
 	{ 0x414c4720, 0x0f, 0, "ALC650", 	0 },
 	{ 0x414c4752, 0x0f, 0, "ALC250",	0 },
-	{ 0x414c4760, 0x0f, 0, "ALC655",	0 },
+	{ 0x414c4760, 0x0f, 0, "ALC655",	alc655_patch },
 	{ 0x414c4770, 0x0f, 0, "ALC203",	0 },
 	{ 0x414c4780, 0x0f, 0, "ALC658",	0 },
 	{ 0x414c4790, 0x0f, 0, "ALC850",	0 },
@@ -403,6 +406,12 @@
 	return codec->caps;
 }
 
+u_int32_t
+ac97_getsubvendor(struct ac97_info *codec)
+{
+	return codec->subvendor;
+}
+
 static int
 ac97_setrecsrc(struct ac97_info *codec, int channel)
 {
@@ -642,6 +651,9 @@
 	}
 
 	codec->id = id;
+	codec->subvendor = (u_int32_t)pci_get_subdevice(codec->dev) << 16;
+	codec->subvendor |= (u_int32_t)pci_get_subvendor(codec->dev) &
+	    0x0000ffff;
 	codec->noext = 0;
 	codec_patch = NULL;
 
Index: src/sys/dev/sound/pcm/ac97.h
===================================================================
RCS file: /home/ncvs/src/sys/dev/sound/pcm/ac97.h,v
retrieving revision 1.16.2.1
diff -u -r1.16.2.1 ac97.h
--- src/sys/dev/sound/pcm/ac97.h	30 Dec 2005 19:55:54 -0000	1.16.2.1
+++ src/sys/dev/sound/pcm/ac97.h	19 Apr 2007 04:25:03 -0000
@@ -102,6 +102,7 @@
 u_int16_t ac97_getextmode(struct ac97_info *codec);
 u_int16_t ac97_getextcaps(struct ac97_info *codec);
 u_int16_t ac97_getcaps(struct ac97_info *codec);
+u_int32_t ac97_getsubvendor(struct ac97_info *codec);
 
 u_int16_t ac97_rdcd(struct ac97_info *codec, int reg);
 void	  ac97_wrcd(struct ac97_info *codec, int reg, u_int16_t val);
Index: src/sys/dev/sound/pcm/ac97_patch.c
===================================================================
RCS file: /home/ncvs/src/sys/dev/sound/pcm/ac97_patch.c,v
retrieving revision 1.3.2.1
diff -u -r1.3.2.1 ac97_patch.c
--- src/sys/dev/sound/pcm/ac97_patch.c	30 Dec 2005 19:55:54 -0000	1.3.2.1
+++ src/sys/dev/sound/pcm/ac97_patch.c	19 Apr 2007 04:25:03 -0000
@@ -56,3 +56,17 @@
 	ac97_wrcd(codec, AC97_MIXEXT_CLFE, 0x0000);
 	ac97_wrcd(codec, 0x64, 0x7110);
 }
+
+void alc655_patch(struct ac97_info* codec)
+{
+	switch (ac97_getsubvendor(codec)) {
+	case 0x01311462:
+	case 0x01611462:
+	case 0x03511462:
+	case 0x00611462:
+		ac97_wrcd(codec, 0x7a, ac97_rdcd(codec, 0x7a) & 0xfffd);
+		break;
+	default:
+		break;
+	}
+}
Index: src/sys/dev/sound/pcm/ac97_patch.h
===================================================================
RCS file: /home/ncvs/src/sys/dev/sound/pcm/ac97_patch.h,v
retrieving revision 1.3.2.1
diff -u -r1.3.2.1 ac97_patch.h
--- src/sys/dev/sound/pcm/ac97_patch.h	30 Dec 2005 19:55:54 -0000	1.3.2.1
+++ src/sys/dev/sound/pcm/ac97_patch.h	19 Apr 2007 04:25:03 -0000
@@ -30,3 +30,4 @@
 void ad1886_patch(struct ac97_info*);
 void ad198x_patch(struct ac97_info*);
 void cmi9739_patch(struct ac97_info*);
+void alc655_patch(struct ac97_info*);