[iBook] ibook G4 combo drive problem

[joe]

My niece has an iBook G4 (14" I think)--slot loading combo drive.   
When she puts a disk in, it stays on the fast spin and never mounts.   
The only way she can eject the disk is to restart the computer.

Any ideas of what I should look at?   I was thinking to use disk  
utility to see if it shows there.  Otherwise--maybe cables that  
aren't fully seated?

Should I start thinking to replace the drive?

I haven't even looked at it yet.  I wanted to get whatever info I  
could before I check it out.

Joe