logic 7 quits when using AU instruments

[seeroos]

Hi does any body got the same problem and has the answer ??
I got a problem with logic 7 when i use any plug ins from AU instruments list the logic quits without any pre warning and I lose my data most of the time I don't way ??
I use FXpansion V1.50.02 relaxed and logic 7.0.1 G5 DP 2.5 GHZ osx 10.3.9
note:I don't get any problems when I use any plug in from Logic List like mostly I use EXs24 and ES 2.
Thanks
seeroos