You might want to give the SoundTrack Pro spectrum analyzer/editor a try. Here’s a tutorial, and it’s explained in teh STP manual. In theory, it allows you to analyze and then erase just the part of the audio spectrum where you problem sound lies. I haven’t actually used it myself, but it worked in a demo I saw.
https://www.zoom-in.com/apple/music/blog/2008/02/quicktip_soundtrack_pro_2_audio_file_projects_frequency_spectrum
David Roth Weiss
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