diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c
index f119a41..7c83bab 100644
--- a/sound/usb/mixer_quirks.c
+++ b/sound/usb/mixer_quirks.c
@@ -885,6 +885,11 @@
 	return changed;
 }
 
+static void kctl_private_value_free(struct snd_kcontrol *kctl)
+{
+	kfree((void *)kctl->private_value);
+}
+
 static int snd_ftu_create_effect_switch(struct usb_mixer_interface *mixer,
 	int validx, int bUnitID)
 {
@@ -919,6 +924,7 @@
 		return -ENOMEM;
 	}
 
+	kctl->private_free = kctl_private_value_free;
 	err = snd_ctl_add(mixer->chip->card, kctl);
 	if (err < 0)
 		return err;