i have a memorex dvd burner which comes with roxio cd/dvd burner, and when ever i put either a cd or dvd into the drive, it still says "insert blank disk." it use to work fine, but now i don't know wuts up...the troubleshooting guide says that maybe the drive isn't hooked up, but i can watch and play cd's and dvd's...also when i use Nero, it says that there isn't a disk...can anyone help me out?