Zoom TAC-2R fixes the latency issue with speaker position estimation but my D100 DAC appears to be sample drifting enough to make it impossible to finish the last 10 calibration measurements. Have to get some adapter cables to hook the Zoom outputs up directly to my speaker amps thus using the thunderbolt interface for both ADC and DAC. It is quite a challenge to get this thing calibrated with their very picky software. I'd say it is trying to be too phase precise in what is ultimately a simple EQ non-phase setting to optimize around a target listening space of about 4' x 4'. Really I don't need perfect flat, not in this room, maybe a studio but certainly not this room. Anything even close would do unfortunately it doesn't let you accept what you can get and just make the file from it. It has to pass all 25 measurement spots and a few more.