got some problems with slim ps2....

Hi all...
I modded my ps2 with a matrix infinity earlier in the year. Since then Ive had a few weird problems. Some times my PS2 locks up and doesnt respond to the power button. Recently, Ive had a problem where my 9 month old ps2 has begun grinding when the door is opened or started. The grinding is inconsistent also. Some times when I play I have no problems whatsoever. I opened up the lid to observe it and saw that the laser is pinned up agains the spindle. When I tried to push it back towards the outside, It quickly returned to the center and kept on grinding. I became suspicious about the chip because I havent had an read errors, and by the way the laser is being guided, it logically didnt seem like it had anything to do with optics. I cleaned the laser with rubbing alcohol and blew out the case with compressed air anyways to no avail. When I opened up the case to inspect the chip, I noticed that the "sx" wire was routed directly to a corner prong of the CPU. I looked around for installation guides for my V14 with GH-040-52 Motherboard but wasnt able to find an exact match. But every install guide I was able to find didnt have that wire routed in that fashion. Is there any possibility that the issues Im having are related to the chip? If not then why the griding?

Any help is greatly appreciated!!!
Thanks,
Benjie

I found that before I turn on the PS2, if I move the laser tracking the outside of the disc it loads perfectly. It appears that the ps2 doesnt know where the laser is in relation to the disc. Is this a symptom of any common problem? Any suggestions?

Thanks,
Benjie