After a while it proved that problem is with the base band on the motherboard.
Removed hardware part of the base band , and put another one... it was a bit difficult because from the other side of the motherboard is ROM and because of the heat it removed also, so it had to be glued again.
After a while i installed again SLIMKAT and problems continued..
Phone froze, wasnt able to call because ACTIVITY PHONE ISNT RESPONDING, and it froze the phone every few calls, and it had to be rebooted, even that didnt helped sometimes, so batery had to go out.
Wiped Cash Partition, nothing happened, Wiped Cash and Dalwik, nothing happened...
Found somewhere that CONTACT SYNC and Facebook Contact sync disableing will help and guess what, it did...
Disabled all Contact Sync and for now everything is ok...