diff --git a/src/add-ons/kernel/drivers/audio/usb_audio/usb_audio.c b/src/add-ons/kernel/drivers/audio/usb_audio/usb_audio.c
index 0f34f13246..57514ef8cb 100644
--- a/src/add-ons/kernel/drivers/audio/usb_audio/usb_audio.c
+++ b/src/add-ons/kernel/drivers/audio/usb_audio/usb_audio.c
@@ -40,6 +40,8 @@ static status_t device_write(void *cookie, off_t pos, const void *data, size_t *
 #define TS	10 // was 4 /* 4 ms buffers */
 #define NB	2
 
+int32 api_version = B_CUR_DRIVER_API_VERSION;
+
 int qs_out = QS_OUT;
 
 typedef struct audiodev audiodev;