Not sure if i understood you right... are you saying the disc cant be ejected ?, or it ejects normally ?
If you can hear the disc spinning it means that the mechanical parts (gears, levers etc...) are working fine, as well as the motors and the disc presence detector led/s i mentioned
There is another audio test you should do

eject the disc and get close to the drive (stick your ear on top of the PS3 case), then insert the disc and try to count how many times it does a "click" sound
That "click" sound that happens inmediatly after inserting a disc is the laser lens moving up and down to "focus" on the disc surface
A healthy laser should be able to start reading the disc with just 2 or 3 "clicks"
But a burned laser is going to repeat the "click" many times (i dont remember how many, but more than 5)