Topic: 0dbfs vs clipping in totalmix fx

Hello, I am a Fireface UC user and have a question regarding the OVER indication in totalmix. Coming off my hardware chain, i find that when testing for the maximum output level into the firefaceUC, totalmix will often show as hitting 0.0 but it takes a bit more juice before i get the "clip" indication. Is there a few DB's of headroom left over before clipping occurs? does the converter have some sort of limiting as a safety before conversion?

I find it a bit puzzling, i didn't see any other posts on this but perhaps i wasn't searching the right keywords. perhaps it is in one of the many versions of the manual out there but i don't recall this subject from when i last went thru it.

If anyone knows what this is about, please tune me in!

thanks