FWIW, I don't think ACW changes the audio at all, but rather the visual grid (time line or tempo/beats) behind the audio display as well as (maybe) the chord layout.

1. Do you actually hear a change?
2. Is this in BiaB or RB?

I know in RB it is possible that the visual scale can change (making waveforms look bigger/smaller) but it doesn't actually change the volume, just the display.

There are 2 +/- icons in the ACW that affect this. One is for display over time (zooms in over time) and the other is for the height scale, which may make transients look larger/smaller, but again these occur in the display, not the actual wavefile(s).

In my experience, the ACW creates a temporary audio file to work with, then sends the tempo/chord change data back to the apps without actually writing over the original audio.

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