EXS 24 Logic Sampler Users Group

hi-

hopefully someone can help me with this:

when i create a sampler instrument, everything works great until i 
close logic and reopen it.  then, my sampler instruments output 
basically white noise.  the original aiff files are completely intact, 
and factory settings work fine.  as you can imagine, this is extremely 
frustrating - i'm wondering if i'm missing something or if anyone else 
has encountered this problem.

i'm using logic pro 6.4.1 on panther with an emi 6|2 soundcard.

thanks-bhob