I am editing a project in which many interviews have been shot in office buildings and hotels with high humm, usually A-C, in the background. I have been unable to filter out the A-C without affecting the voice.

Any recommendations on audio EQ settings? Maybe my settings in Clean Up are incorrect.

(CS-3)

You probably have already done this, but I think that if you have a section where there is nothing but the AC noise, you could capture/identify a bit of that to tell Soundbooth exactly what to remove, hopefully without affecting anything else.

I've never had great success removing noise. Generally what happens is when you reduce the gain for the frequency range the noise is in, it effects the voice, either by losing the base or cutting the highs. Take it all out, then it sounds unnatural, take a little and you still hear the noise, only slightly less.

Just get a lav mic for next time.

Different side of things but Apple's SoundTrack Pro has an amazing room tone remover. Works by analyzing the tone, then employs phase cancellation.

Might want to look into that if you are stuck.
-C

I have a great program that I use often.. (Im PC based) to remove noises etc.
Try the trail version. iZotope RX.