When I click the CD Drive button on the side, it seems to respond fine, showing the green beeps and opening. When I put in a CD or DVD, the driver sounds like it's responding: the green light flashes on the side (indicating that the CD is recognized).However, nothing happens otherwise. The CD is not recognized and you can't hear the "whirring" inside the laptop of the CD spinning/playing. What might be the culprit here? Do I have to replace the whole drive?