looks like the newer version of the app, (1.02 labeled "MMA-A") actually implements the lock feature correctly. i can adjust the level slider in metarecorder but it has no function if the dpa app is locked.
as far as i understand it (wild ass guess), there is only one gain stage that is being adjusted via core audio whether you use either app.so im not sure there is really a "unity gain" setting
this is what a DPA rep told me last year in regard to setting level with dpa app vs metarecorder. emphasis mine
me:
My setup acts unpredictably sometimes like just now I hooked it up and set the levels, which were adjustable in the DPA app, then I locked it and went to MetaRecorder and then once I started recording none of the levels were adjustable in either of the apps.I get this lock up once every handful of times I do it. It only happens when I hit the lock button. Other times I hit the lock button and it does nothing at all, the apps levels are still adjustable and in the other app. Just now I connected, didn’t lock, started recording with MetaRecorder and levels were adjustable in the app, but did not match dpa app levels. Sometimes dpa levels sync to recording software, sometimes they do not. Sometimes they are adjustable, sometimes they are not. I am not sure which levels the DPA app is actually supposed to represent whether that’s analog input levels to the device or whether that is the digital data written relative to 0dbfs. I also have the ear of apogee Support I’m not sure if you’d like to do a conversation with those guys copied on it. Might be useful
DPA:
3rd party app should always be adjustable but the dpa analog input will keep it from clipping in other app
me:
Apogee guys say that that app has no gain so I have to assume at this point it’s directly interfacing with control logic of the dvice itself. I’ve done some other testing and uncovered a couple quirks but for now the sure way to safe recording for me seems to be to plug in the dvice, open up dpa app and make sure levels are set to minimum and that the rolloff is set to off, leave the app unlocked, close it then open up metarecorder and record where I can adjust levels.