usx2y_urb_submit
err = usx2y_urb_submit(playbacksubs, urb, frame);
err = usx2y_urb_submit(capsubs, capsubs->completed_urb, frame);
err = usx2y_urb_submit(capsubs, capsubs->completed_urb, frame);
err = usx2y_urb_submit(capsubs2, capsubs2->completed_urb, frame);