-6dB wit AA2.0 + Edirol UA-25

I use AA2 since few weeks (after 3 years with CE2) with a new Usb interface (Edirol UA-25) and an old Condenser Microphone (Samson C03). I work with a desktop and a laptop, both with the Edirol drivers on and tuned for audio. Recording both in EV and MV the levels are locked at -6dB, even if the VU-meter climbs properly at 0dB. Of course both limiter on soundboard and microphone are off. None of the 8 tabs in AA2 preferences refers to a level limiting function. I've reinstalled the Edirol drivers on both Pc, but the problem remains. I close saying that the tracks, even if abruptly limited at -6dB, doesn’t show distorsion or others faults. Does any have a solution. Thanks in advance to everybody.
UT

Well, this sounds like an Edirol (or its mixer) issue, because Audition doesn't control the levels sent to it at all, certainly in EV. Assuming that you've checked for any driver updates, then I think that you will need to wait for another UA-25 user to see this thread.