diff --git a/firmware/drivers/ata.c b/firmware/drivers/ata.c
index 9f02558..5161bbd 100644
--- a/firmware/drivers/ata.c
+++ b/firmware/drivers/ata.c
@@ -473,7 +473,7 @@
                 break;
 
             case Q_SLEEP:
-                last_disk_activity = current_tick - sleep_timeout;
+                last_disk_activity = current_tick - sleep_timeout + (HZ/2);
                 break;
         }
     }