diff --git a/sound/isa/ad1848/ad1848_lib.c b/sound/isa/ad1848/ad1848_lib.c
index 330b5ced01aad6ba467ab2ab7432c479e0ac259f..18355fd66cb5eecc07334a772cc2d763ad3f9ab7 100644
--- a/sound/isa/ad1848/ad1848_lib.c
+++ b/sound/isa/ad1848/ad1848_lib.c
@@ -236,7 +236,9 @@ static void snd_ad1848_mce_down(struct snd_ad1848 *chip)
 	 * calibration process to start. Needs upto 5 sample periods on AD1848
 	 * which at the slowest possible rate of 5.5125 kHz means 907 us.
 	 */
+	spin_unlock_irqrestore(&chip->reg_lock, flags);
 	msleep(1);
+	spin_lock_irqsave(&chip->reg_lock, flags);
 
 	snd_printdd("(2) jiffies = %lu\n", jiffies);