Traktor 2.5.1 collection issues

in recent times my songs in traktor started to behave strangely.
first i lost all my remix sets from the collection. both the ones I have done myself and those who came with 2.5 .. and some songs that I, for example, played last week has completely disappeared from my collection and I have to add them again and put a new beatgrids. (all my songs in the collection are beatgrided and locked)
I organize all my songs in itunes and have all the playlist in itunes. I have been a traktor user for many years and this has never messed befor. tips on what might be wrong?
for as it is now, I have to always go through all those songs I've thought to play from a playlist just to see that they are in my collection and have beatgrids that is spot on


my setup is
macbook pro i5 (OS X Snow Leopard)
traktor 2.5.1

 

this is the same problem i have one week the songs are there the other they are not but when i look in the folder on my hard drive the songs are there , is there a solution to this problem

 

use 2.6