--- alsa-20040120/alsa-lib/src/pcm/pcm_mmap_old.c	2004-01-20 11:03:28.000000000 +0100

+++ alsa-20040120/alsa-lib/src/pcm/pcm_mmap.c	2004-01-20 13:04:03.000000000 +0100

@@ -462,11 +462,16 @@

 			if (i->u.shm.area) {

 				snd_shm_area_destroy(i->u.shm.area);

 				i->u.shm.area = NULL;

-			} else {

-				err = shmdt(i->addr);

-				if (err < 0) {

-					SYSERR("shmdt failed");

-					return -errno;

+				if (pcm->access == SND_PCM_ACCESS_MMAP_INTERLEAVED ||

+				    pcm->access == SND_PCM_ACCESS_RW_INTERLEAVED) {

+					unsigned int c1;

+					for (c1 = c + 1; c1 < pcm->channels; c1++) {

+						snd_pcm_channel_info_t *i1 = &pcm->mmap_channels[c1];

+						if (i1->u.shm.area) {

+							snd_shm_area_destroy(i1->u.shm.area);

+							i1->u.shm.area = NULL;

+						}

+					}

 				}

 			}

 			break;