I have Forscan on my laptop and a wired odb switched dongle. I used it to make my fog lights stay on when the high beams are on.I tried making a line change to what I was told was the way to disable the factory bass rolloff, it made absolutely no difference.
To go back into the computer I would need to flash the car back to stock, Forscan won't recognize the car with the tune. I got the warranty friendly Ford performance calibration kit with the procal programmer, it's slow to flash and after you put the tune back on the car takes a week or more to relearn everything and start performing. I would prefer the Cobb unit but my dealership would not.
I remember reading something about the factory head unit have unclipped output all the way to max volume when in low level mode and a voltage near 4 volts.
I may look into this further when the weather warms up.
I'm happy to see that a proper DSP will work with the factory head unit, I will do some research on the models suggested and pick one that fits my needs.
I am a little disappointed with lc2i after all the hype I heard about how it fixes bass frequencies, to my experience it is a terrific LOC but the accubass is just a dynamic bass booster centered around 50hz.