diff --git a/sound/drivers/aloop.c b/sound/drivers/aloop.c
index 64ef03b2d579..aa0d2fcb1a18 100644
--- a/sound/drivers/aloop.c
+++ b/sound/drivers/aloop.c
@@ -336,37 +336,43 @@ static bool is_access_interleaved(snd_pcm_access_t access)
 
 static int loopback_check_format(struct loopback_cable *cable, int stream)
 {
+	struct loopback_pcm *dpcm_play, *dpcm_capt;
 	struct snd_pcm_runtime *runtime, *cruntime;
 	struct loopback_setup *setup;
 	struct snd_card *card;
+	bool stop_capture = false;
 	int check;
 
-	if (cable->valid != CABLE_VALID_BOTH) {
-		if (stream == SNDRV_PCM_STREAM_PLAYBACK)
-			goto __notify;
-		return 0;
-	}
-	runtime = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->
-							substream->runtime;
-	cruntime = cable->streams[SNDRV_PCM_STREAM_CAPTURE]->
-							substream->runtime;
-	check = runtime->format != cruntime->format ||
-		runtime->rate != cruntime->rate ||
-		runtime->channels != cruntime->channels ||
-		is_access_interleaved(runtime->access) !=
-		is_access_interleaved(cruntime->access);
-	if (!check)
-		return 0;
-	if (stream == SNDRV_PCM_STREAM_CAPTURE) {
-		return -EIO;
-	} else {
-		snd_pcm_stop(cable->streams[SNDRV_PCM_STREAM_CAPTURE]->
-					substream, SNDRV_PCM_STATE_DRAINING);
-	      __notify:
-		runtime = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->
-							substream->runtime;
-		setup = get_setup(cable->streams[SNDRV_PCM_STREAM_PLAYBACK]);
-		card = cable->streams[SNDRV_PCM_STREAM_PLAYBACK]->loopback->card;
+	scoped_guard(spinlock_irqsave, &cable->lock) {
+		dpcm_play = cable->streams[SNDRV_PCM_STREAM_PLAYBACK];
+		dpcm_capt = cable->streams[SNDRV_PCM_STREAM_CAPTURE];
+
+		if (cable->valid != CABLE_VALID_BOTH) {
+			if (stream == SNDRV_PCM_STREAM_CAPTURE || !dpcm_play)
+				return 0;
+		} else {
+			if (!dpcm_play || !dpcm_capt)
+				return -EIO;
+			runtime = dpcm_play->substream->runtime;
+			cruntime = dpcm_capt->substream->runtime;
+			if (!runtime || !cruntime)
+				return -EIO;
+			check = runtime->format != cruntime->format ||
+			runtime->rate != cruntime->rate ||
+			runtime->channels != cruntime->channels ||
+			is_access_interleaved(runtime->access) !=
+			is_access_interleaved(cruntime->access);
+			if (!check)
+				return 0;
+			if (stream == SNDRV_PCM_STREAM_CAPTURE)
+				return -EIO;
+			else if (cruntime->state == SNDRV_PCM_STATE_RUNNING)
+				stop_capture = true;
+		}
+
+		setup = get_setup(dpcm_play);
+		card = dpcm_play->loopback->card;
+		runtime = dpcm_play->substream->runtime;
 		if (setup->format != runtime->format) {
 			snd_ctl_notify(card, SNDRV_CTL_EVENT_MASK_VALUE,
 							&setup->format_id);
@@ -389,6 +395,10 @@ static int loopback_check_format(struct loopback_cable *cable, int stream)
 			setup->access = runtime->access;
 		}
 	}
+
+	if (stop_capture)
+		snd_pcm_stop(dpcm_capt->substream, SNDRV_PCM_STATE_DRAINING);
+
 	return 0;
 }