I'm here again!
hi mate. this is my idea. first check the uvw mapping of usb front. then it would be because of refelction map and value. change the coordinate mapping type of reflection map. decrease the value of reflection. and try to use another backgroud. (it seems that usb front is completely reflecting the white background. so it turns white.)
edit: it's just my idea. i don't know if it works or not.