Can no longer burn via Nero, or WinXP

When trying to burn to my ‘crw1610a’ I keep getting the message: “Please insert an empty disc to write to…” –my CD then ejects from the ‘ASUS CRW 1610A’.
This happens when I try to use both Windows in-built burning capabilities –and/or if I use NERO.
-It used to burn flawlessly via Nero or Windows.
Any idea what the problem is now?
I’m double posting this in Software and Hardware forums as I’m not sure if it is a Hardware, or Software problem.
Thanks for your time, and for any suggestions.
Yours,
522.