Problem fixed!!!
I will post the full thing in case someone comes to the forums with the same issue.
Hu card sound: it was fine with the console in normal position or standing on a side.
Audio CD: In normal position seems like the inner tracks sound almost fine but with outer tracks there were lots of glitches and cd lens moving back and forth from inner to outer tracks. Standing on one side all the audio tracks were ok. While listening audio CD if the console is moved from stand on a side to its normal position sound glitches appear again.
CD games: It seems there is problems just with the audio tracks, the FX sounds are ok.
I played with the lens potentiometer again but i wasnt able to find a point with no audio glitches.
I moved the potentiometer that seems to have less audio glitches and then tried to adjust the board potentiometers.
I just moved VR101 pot a bit to the right and the problem was fixed.
CD games now load very fast and not a single audio glitch when playing games or listening audio CD's
Thanks everyone for your help!