Can keyframes not be made on some audio effects?
 

I have a clip where I want to add a silly audio sound where the pitch gradually increases from low to high. I added the PitchShift audio effect (in CS3) to my clip in the audio track but no matter what I do it wont add a keyframe for the pitch. It only lets me raise or lower the pitch for the entire clip. Am I doing something wrong or is this really not possible for some effects? It seems like this would be able to be done.

Thanks,
Scott

What about chopping the audio clip into different pieces, then pitch shift each piece individually. Time consuming, but could work great.

I was thinking about that, but I was afraid it wouldn't be a smooth, continuous increase in pitch and that it'd be more like taking steps up in pitch. But I might just have to do that because I'm starting to think that's the only solution.