translating RT effects to actions

'm trying to clean up some workshop recordings, using SoundSoap 2 to remove noise and Compressor to even out the volume. I get a good result using both as Real Time effects, but when I try to turn them into Actions the results degrade significantly. This is true whether I apply each one separately (with the same settings I'm using in the RT effect) or bounce the RT effects into an Action. SoundSoap, in particular, does not translate well. The Action seems to introduce artifacts not present in the RT effect.

I thought that RT effects and Actions should apply the same transformations to the underlying sound, but apparently this isn't the case. Am I doing something wrong, or is this an inherent limitation in the application?

Ralph