please Need HELP with console

[papero]

Hi all, I have a PS2 modified with the NO solder/plug in mod chip (the one that requires Gameshark to boot). It has been working fine for 1 1/2 year up untill a few days ago when, after a month of disuse, it started giving me problems booting up. The console makes weird -stuck like- noises while trying to boot the games(both originals and backups) and never proceeds. If this happens while a game is running, the game freezes up. SOmentimes the console has even problems recognizing the disks as PS2 disks. SOunds like an engine problem, as if the motor gets stuck and disrupts the laser reading of the disk but this is just my unexperienced impression. WHat can I do to identify and possibly solve this problem? Please, any help is gratly appreciated !!!
ThanXXX