> Does anyone know what the problem could be.
It's that you didn't buy a NEC 3550A like everyone told you to. 🙂
Besides that,
- the disc might be jammed such that it can't eject
- the tray might have "jumped the tacks" in its push/pull mechanism
- other mechanical problem
For the last 2 problems, try the ejection hole again with the power off and a straightened out paperclip instead of a pencil. I had to do this once and the paper clip needed to be pushed in much farther than I'd expected to release the tray.