diff --git a/sys/dev/sound/pcm/dsp.c b/sys/dev/sound/pcm/dsp.c
--- a/sys/dev/sound/pcm/dsp.c
+++ b/sys/dev/sound/pcm/dsp.c
@@ -260,6 +260,12 @@
 	PCM_LOCK(d);
 	PCM_WAIT(d);
 	PCM_ACQUIRE(d);
+	if (!DSP_REGISTERED(d)) {
+		PCM_RELEASE(d);
+		PCM_UNLOCK(d);
+		PCM_GIANT_EXIT(d);
+		goto skip;
+	}
 
 	rdch = priv->rdch;
 	wrch = priv->wrch;
diff --git a/tests/sys/sound/hotunload.sh b/tests/sys/sound/hotunload.sh
--- a/tests/sys/sound/hotunload.sh
+++ b/tests/sys/sound/hotunload.sh
@@ -41,6 +41,7 @@
 		cat /dev/random >/dev/dsp.dummy &
 		cat /dev/dsp.dummy >/dev/null &
 	done
+	killall cat
 	kldunload -n snd_dummy
 }
 hotunload_cleanup()