--- esound-0.2.36/esddsp.c
+++ esound-0.2.36/esddsp.c
@@ -47,6 +47,7 @@
 #include <sys/time.h>
 #include <stdio.h>
 #include <pthread.h>
+#include <errno.h>
 
 #ifdef HAVE_MACHINE_SOUNDCARD_H
 #  include <machine/soundcard.h>
@@ -336,6 +337,17 @@
       fmt |= (*arg) ? ESD_STEREO : ESD_MONO;
       break;
 
+#ifdef SNDCTL_DSP_CHANNELS
+    case SNDCTL_DSP_CHANNELS:
+      if (*arg != 1 && *arg != 2) {
+	errno = ENOTSUP;
+	return -1;
+      }
+      fmt &= ~ESD_MONO;
+      fmt |= (*arg == 2) ? ESD_STEREO : ESD_MONO;
+      break;
+#endif
+
     case SNDCTL_DSP_GETBLKSIZE:
       if (mmapemu)
       	*arg = MMAPEMU_FRAGSIZE;