The drive used in the studio 1535 is a sony optiarc dvd drive.
The actual drive does not have a front cover, however the cover is part of the shell of the laptop.
Take a flashlight and look into the slot where the disc goes.
You should see a metal piece on one side of the drive. This keeps the disc from flying out of the drive.
You need to push the metal piece down with a paperclip or something. This metal piece usually gets caught, so all you do is push down and the disc comes right out
The problem is caused by pressure on the optical drive.
Pick up your laptop from the left side from now on, so that you do not put pressure on your optical drive