Hi, I have an iMac OX 10.9.5 (Maverick). My problem is that my blank DVDs keep getting ejected. I've tried burning them with both iDVD and a program called Burn. I've tried inserting the DVD before hitting the burn button and also after. I've tried inserting one without any application open, and the blank disc doesn't register on-screen, nor do I get a pop-up asking me what to do with it. It just "grinds" inside the drive, then gets spit out. The DVDs are Memorex 16X DVD-R. Admittedly, I haven't tried burning anything for a long time. It used to work when I had OX 6-something. Any suggestions/advice? P.S. DVD-R is one of the allowable formats listed under "About this Mac." Thanks!