diff --git a/sys/dev/sound/pcm/channel.h b/sys/dev/sound/pcm/channel.h
--- a/sys/dev/sound/pcm/channel.h
+++ b/sys/dev/sound/pcm/channel.h
@@ -260,7 +260,7 @@
 int chn_poll(struct pcm_channel *c, int ev, struct thread *td);
 
 struct pcm_channel *chn_init(struct snddev_info *d, struct pcm_channel *parent,
-    kobj_class_t cls, int dir, int num, void *devinfo);
+    kobj_class_t cls, int dir, void *devinfo);
 void chn_kill(struct pcm_channel *c);
 void chn_shutdown(struct pcm_channel *c);
 int chn_release(struct pcm_channel *c);
diff --git a/sys/dev/sound/pcm/channel.c b/sys/dev/sound/pcm/channel.c
--- a/sys/dev/sound/pcm/channel.c
+++ b/sys/dev/sound/pcm/channel.c
@@ -1159,7 +1159,7 @@
 
 struct pcm_channel *
 chn_init(struct snddev_info *d, struct pcm_channel *parent, kobj_class_t cls,
-    int dir, int num, void *devinfo)
+    int dir, void *devinfo)
 {
 	struct pcm_channel *c;
 	struct feeder_class *fc;
@@ -1169,7 +1169,6 @@
 
 	PCM_BUSYASSERT(d);
 	PCM_LOCKASSERT(d);
-	KASSERT(num >= -1, ("invalid num=%d", num));
 
 	switch (dir) {
 	case PCMDIR_PLAY:
@@ -1207,7 +1206,7 @@
 		goto out1;
 	}
 
-	unit = (num == -1) ? 0 : num;
+	unit = 0;
 
 	if (*pnum >= max || unit >= max) {
 		device_printf(d->dev, "%s(): unit=%d or pnum=%d >= than "
@@ -1220,12 +1219,6 @@
 	CHN_FOREACH(c, d, channels.pcm) {
 		if (c->type != type)
 			continue;
-		if (unit == c->unit && num != -1) {
-			device_printf(d->dev,
-			    "%s(): channel num=%d already allocated\n",
-			    __func__, unit);
-			goto out1;
-		}
 		unit++;
 		if (unit >= max) {
 			device_printf(d->dev,
diff --git a/sys/dev/sound/pcm/sound.c b/sys/dev/sound/pcm/sound.c
--- a/sys/dev/sound/pcm/sound.c
+++ b/sys/dev/sound/pcm/sound.c
@@ -165,7 +165,7 @@
 	/* no channel available */
 	if (!(vchancount > 0 && vchancount < snd_maxautovchans))
 		return (err);
-	err = vchan_setnew(d, direction, vchancount + 1, -1);
+	err = vchan_setnew(d, direction, vchancount + 1);
 	if (err == 0) {
 		retry = true;
 		goto retry_chnalloc;
@@ -274,7 +274,7 @@
 	PCM_BUSYASSERT(d);
 
 	PCM_LOCK(d);
-	ch = chn_init(d, NULL, cls, dir, -1, devinfo);
+	ch = chn_init(d, NULL, cls, dir, devinfo);
 	if (!ch) {
 		device_printf(d->dev, "chn_init(%s, %d, %p) failed\n",
 		    cls->name, dir, devinfo);
diff --git a/sys/dev/sound/pcm/vchan.h b/sys/dev/sound/pcm/vchan.h
--- a/sys/dev/sound/pcm/vchan.h
+++ b/sys/dev/sound/pcm/vchan.h
@@ -32,7 +32,7 @@
 
 extern int snd_maxautovchans;
 
-int vchan_create(struct pcm_channel *, int);
+int vchan_create(struct pcm_channel *);
 int vchan_destroy(struct pcm_channel *);
 
 #ifdef SND_DEBUG
@@ -47,7 +47,7 @@
 	sndbuf_getfmt((c)->bufhard) != (c)->parentchannel->format ||	\
 	sndbuf_getspd((c)->bufhard) != (c)->parentchannel->speed))
 
-int vchan_setnew(struct snddev_info *, int, int, int);
+int vchan_setnew(struct snddev_info *, int, int);
 void vchan_setmaxauto(struct snddev_info *, int);
 
 void vchan_initsys(device_t);
diff --git a/sys/dev/sound/pcm/vchan.c b/sys/dev/sound/pcm/vchan.c
--- a/sys/dev/sound/pcm/vchan.c
+++ b/sys/dev/sound/pcm/vchan.c
@@ -339,7 +339,7 @@
 			cnt = 0;
 		if (cnt > SND_MAXVCHANS)
 			cnt = SND_MAXVCHANS;
-		err = vchan_setnew(d, direction, cnt, -1);
+		err = vchan_setnew(d, direction, cnt);
 	}
 
 	PCM_RELEASE_QUICK(d);
@@ -664,7 +664,7 @@
 				"play.vchanrate" : "rec.vchanrate"
 
 int
-vchan_create(struct pcm_channel *parent, int num)
+vchan_create(struct pcm_channel *parent)
 {
 	struct snddev_info *d;
 	struct pcm_channel *ch;
@@ -700,7 +700,7 @@
 	}
 
 	/* create a new playback channel */
-	ch = chn_init(d, parent, &vchan_class, direction, num, parent);
+	ch = chn_init(d, parent, &vchan_class, direction, parent);
 	if (ch == NULL) {
 		PCM_UNLOCK(d);
 		CHN_LOCK(parent);
@@ -933,7 +933,7 @@
 }
 
 int
-vchan_setnew(struct snddev_info *d, int direction, int newcnt, int num)
+vchan_setnew(struct snddev_info *d, int direction, int newcnt)
 {
 	struct pcm_channel *c, *ch, *nch;
 	struct pcmchan_caps *caps;
@@ -959,10 +959,9 @@
 		return (EINVAL);
 
 	if (newcnt > vcnt) {
-		KASSERT(num == -1 ||
-		    (num >= 0 && num < SND_MAXVCHANS && (newcnt - 1) == vcnt),
-		    ("bogus vchan_create() request num=%d newcnt=%d vcnt=%d",
-		    num, newcnt, vcnt));
+		KASSERT((newcnt - 1) == vcnt,
+		    ("bogus vchan_create() request newcnt=%d vcnt=%d",
+		    newcnt, vcnt));
 		/* add new vchans - find a parent channel first */
 		ch = NULL;
 		CHN_FOREACH(c, d, channels.pcm) {
@@ -1004,7 +1003,7 @@
 		ch->flags |= CHN_F_BUSY;
 		err = 0;
 		while (err == 0 && newcnt > vcnt) {
-			err = vchan_create(ch, num);
+			err = vchan_create(ch);
 			if (err == 0)
 				vcnt++;
 			else if (err == E2BIG && newcnt > vcnt)
@@ -1018,8 +1017,6 @@
 		if (err != 0)
 			return (err);
 	} else if (newcnt < vcnt) {
-		KASSERT(num == -1,
-		    ("bogus vchan_destroy() request num=%d", num));
 		CHN_FOREACH(c, d, channels.pcm) {
 			CHN_LOCK(c);
 			if (c->direction != direction ||
@@ -1061,14 +1058,14 @@
 		return;
 
 	if (num >= 0 && d->pvchancount > num)
-		(void)vchan_setnew(d, PCMDIR_PLAY, num, -1);
+		(void)vchan_setnew(d, PCMDIR_PLAY, num);
 	else if (num > 0 && d->pvchancount == 0)
-		(void)vchan_setnew(d, PCMDIR_PLAY, 1, -1);
+		(void)vchan_setnew(d, PCMDIR_PLAY, 1);
 
 	if (num >= 0 && d->rvchancount > num)
-		(void)vchan_setnew(d, PCMDIR_REC, num, -1);
+		(void)vchan_setnew(d, PCMDIR_REC, num);
 	else if (num > 0 && d->rvchancount == 0)
-		(void)vchan_setnew(d, PCMDIR_REC, 1, -1);
+		(void)vchan_setnew(d, PCMDIR_REC, 1);
 }
 
 static int