What version of AI?
It works fine on CS 5
CS5. there are other hiccups that I'm having as well, it started with CS4 and has continued with CS5. I really don't know if the hiccups are hardware or software related.
Hearing the other hiccups might help the helpers help.
The other hiccup that has been happening since CS4, is a crash report when I quit an application (ID, PS, AI, DW, FW, etc). Most of the time, I wonder if OS 10.6 has a bit of code that does not like the CS versions. It seems that it started happening when I installed 10.6. When I got CS5, I had to install Rosetta, because there's a software switch in 10.6 that requires it in order for After Effects to run.