diff --git a/sound/usb/usx2y/usx2yhwdeppcm.c b/sound/usb/usx2y/usx2yhwdeppcm.c
index 9acef9d9054376d9e1c5d0f2c93ac7803802dc3e..20708d2ffb6a35d7046bb725f43c9f1511d89c01 100644
--- a/sound/usb/usx2y/usx2yhwdeppcm.c
+++ b/sound/usb/usx2y/usx2yhwdeppcm.c
@@ -632,7 +632,7 @@ static int usX2Y_pcms_lock_check(struct snd_card *card)
 		for (s = 0; s < 2; ++s) {
 			struct snd_pcm_substream *substream;
 			substream = pcm->streams[s].substream;
-			if (SUBSTREAM_BUSY(substream))
+			if (substream && SUBSTREAM_BUSY(substream))
 				err = -EBUSY;
 		}
 	}