I've been using the ADI-2 Pro with ProTools for years. Although I don't use Ableton, I've not had a problem with ProTools. The output seems consistent with anything else coming out of the Mac.
Just to ask, are you using the ADI-2 within an Aggregate Audio device or direct? I typically set it up within an Aggregate which includes my USB mic (for talkback) as well as the built-in Mac speakers. This allows me to always keep the Aggregate as the I/O even if the ADI-2 is powered off... I can route to the internal speakers just for a quick listen/check and I don't have to power on my Genelecs.
One thing to confirm is the reference level settings within ProTools prefs. I do everything at -20dBFS since I work mainly in Television.
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Eric Seaberg • San Diego, CA • USA
A.E.S. • S.M.P.T.E. • S.P.A.R.S. • I.E.E.E.