Audio Studio 10 doesn’t appear to have the noise reduction plugin that you can get for the Pro version so I’d stick with Audacity. Do all your work in Audio Studio first, save it as a WAV file and then import that into Audacity for noise reduction.
Movie Studio should have volume envelopes. Look in the online help file to confirm this. If it does, all you need to do is apply a very small envelope at the click point to drastically reduce or eliminate it.