I kind of solved it. The story is this: After a thunderstorm we lost the link to the CS1000E in our hospital, everything seemed normal, but the usual LD96 dis dch + ld60 disl, enll didn´t work. I found a Trunk line card damaged and replaced it and found that some genius a while back tought it was not necessary to put the CO lines tru line protectors. I think a lightning got tru the trunk card and messed up with the PBX.
ssck report was normal but I suspected the clock, so I set it to Free run and the PRI connected for like 1 call and then down again, so I tried TRCK PCK and it reported: "Supposed to track on primary but hardware is free run" again and again to no avail, So I left it FR and we had to ENLL about every 2 hrs while I figured out a permanent solution.
Based on that I tought it was a faulty CC daughtercard (wich We don´t have spares) Then is when I found the NTAK10DC and in my despair I tought it could be a replacement only after firebirdscrambler post I saw the big DTI label on the front so that's why my stupid question.
Finally after a couple of days I tried again TRCK PCK and after 3 times it got locked to primary and after the whole weekend lcnt reports 0 errors.
So I still don´t know why it was so hard to lock the clock, but we are fixing the CO's wiring.
Thanks a lot to All for Your input.