memset(out, 0, sizeof(out));
- err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, out, sizeof(out), &cnt, USB_TIMEOUT);
+ err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, out, 0, &cnt, USB_TIMEOUT);
if (err && (!silent)) {
fprintf(stderr, "Can't send null frame: %s\n", usb_strerror(err));
return 0;