I have just purchased a new DVD burner. Sony DRU-800A. I have put it in where my DVD-ROM slot was. Problem is the drive door won't open automatically (I have to open it manually) and when I put the software disc in there it won't close and it doesn't even seem to run. I also can't use my CD player either as the door won't open and it won't play. What have I done wrong. I have followed all the directions. Can someone please help me. Thanks so much.