diff --git a/src/device/usbd.h b/src/device/usbd.h
index 3ab6c813f..cf500143a 100644
--- a/src/device/usbd.h
+++ b/src/device/usbd.h
@@ -421,7 +421,7 @@ TU_ATTR_WEAK bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb
 /* Standard AS Isochronous Feedback Endpoint Descriptor(4.10.2.1) */
 #define TUD_AUDIO_DESC_STD_AS_ISO_FB_EP_LEN 7
 #define TUD_AUDIO_DESC_STD_AS_ISO_FB_EP(_ep, _interval) \
-  TUD_AUDIO_DESC_STD_AS_ISO_FB_EP_LEN, TUSB_DESC_ENDPOINT, _ep, (uint8_t) (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_NO_SYNC | TUSB_ISO_EP_ATT_EXPLICIT_FB), U16_TO_U8S_LE(4), _interval
+  TUD_AUDIO_DESC_STD_AS_ISO_FB_EP_LEN, TUSB_DESC_ENDPOINT, _ep, (uint8_t) ((uint8_t)TUSB_XFER_ISOCHRONOUS | (uint8_t)TUSB_ISO_EP_ATT_NO_SYNC | (uint8_t)TUSB_ISO_EP_ATT_EXPLICIT_FB), U16_TO_U8S_LE(4), _interval
 
 // AUDIO simple descriptor (UAC2) for 1 microphone input
 // - 1 Input Terminal, 1 Feature Unit (Mute and Volume Control), 1 Output Terminal, 1 Clock Source