CD or DVD disc constantly ejects at startup
1. Try cleaning the disc. If it is dirty or scratched, it may not mount.
2. Try a known good disc.
3. Disconnect all peripheral devices, especially the mouse in cases where the disc is constantly ejecting. This symptom may be an indication of a failed mouse giving a signal that the mouse is stuck in the down position. Try a known good mouse.
4. Boot from Apple Hardware Test (hold down the “C” key at startup) or boot from the system install CD (use Startup Manager, hold down the Option key at startup).
5. Perform a clean install with the CD that came with the computer.
6. Replace the optical drive cable.
7. Replace the optical drive.
8. Replace the down converter.
9. Replace the logic board.
Optical drive tray won’t accept a CD or DVD
1. Check for obstructions on the optical drive door.
2. Replace the optical drive cable.
3. Replace the optical drive.
4. Replace the down converter.
5. Replace the logic board.