But for the original post, a noise that appear only when exporting… never seen something like that in my life in all the DAW i’ve tested 
maybe a problem with the plugin live mode and rendering state… very strange. Oh yes sometimes some plugs offer different settings for live mode and rendering mode… it can be a possible cause… maybe a weird oversampling setting somewhere you can try to export each track, to find the place where the culprit is, by deduction 