Dear friends,
first of all I want to thanks everybody who had the patience to give me an help in my desperate situation. THANK YOU AGAIN!!!!!!
Now I can say I found the good solution for audio-midi sync problems.
The mother of all my problems was: A WRONG CHIPSET IN MY MOTHERBOARD.

A FRIENDLY ADVICE TO EVERYBODY: IF YOU WANT CHANGE YOUR CONFIGURATION PLEASE CHECK YOUR MOTHERBOARD: YOU MUST USE A BX INTEL!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

IF YOU REMEMBER IN MY PREVIOUS MESSAGES I USED THE ASUS CUV4X MOTHERBOARD (VIA CHIPSET!). WELL, THIS IS A VERY GOOD MOTHERBOARD BUT NOT FOR HEAVY WORKS WITH AUDIO OR VIDEOS.
SO I bought a new motherboard ABIT BX133 (Bx Intel). I installed my applications and MIRACLE! I OPENED CAKEWALK and was running in a perfect WAY (WOW!!!)
I WANT TO EXPLAIN THAT THIS IS NOT MY IMAGINATION.
I found similar advices several times. For example:

1) If you want use the audio card Roland USB
UA30 with every audio program you will find this message on the instructions: PLEASE USE INTEL CHIPSET!

2) If you want use Pro-tools on Windows you can finde the same advice: PLS USE BX440 INTEL or BX810 INTEL !!

3) I have friend who use PC for professional videos. He confirmed me the same thing. Two years ago he started to use PC for videos.
He spent two months because (only on video applications) his PC seemed to be crazy.
He discovered he had to change his motherboard. His New Motherboard has BX INTEL CHIPSET !!!

I'm sure these are not casual things.

BYE BYE.

A. Lazzari