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DAC+ADC Pro alsamixer options document?

I have the HiFiBerry DAC+ADC Pro working to both play and record at the same time on a Pi 3. I'm using the python "sounddevice" library, for example

import sounddevice as sd

dataIN = sd.playrec(dataOUT, fsrate, channels=numRecCh, device=HiFiDev) 

At any rate, my question is about the device settings via "alsamixer". I'm used to simple volume controls, but this card has a large variety of settings. I count 26 different playback settings, from "DSP Program" on over to "Volume Ramp Up Step".  Is there a manual that explains them all? 

Specifically I want to know about the DSP Program settings. Is there one that means "no alteration, play data exactly as it is"? I have five choices, but none of them are clearly that.  I thought the most likely candidate is "Fixed Process Flow" but in that mode, I get no output at all. In "Ringing-less low latency FIR" at least I do get an output.  Note I am not playing any kind of music, this is a technical application. The data is mostly complete silence, with isolated single-cycle, full-amplitude (0 dB FS) pulses of around 5 kHz. Sample rate is 96 kHz.

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