Thanks for answering!
It would be interesting to see what you get from your DiMarzio Evolution pickups. I've used a Ibanez Artcore Semihollow body which had Humbuckers and that one also didn't really get higher than -10 DB with my Babyface Pro. Unfortunately due to a fire, the house I had was lost along with the guitar.
I use Overloud THU and there is a Input Low Sensitivity which they recommend for Single Coil Pickups and High Sensitivity for Humbuckers. It does incread the loudness if I put to High Sensitivity but that is going against the recommendation since I have single coil pickups. It just seems like something is wrong when you can't even with everything maxed out reach a level that the amp software thinks is optimal.
You 're welcome!
I will report back when I try it, as I need to buy a cable to connect my Digimax FS to my Digiface, sometime next week!
Sorry to hear about your house..! And your Ibanez..! Can't even begin to imagine how that felt..
Hope you 've recovered allright!!
Untill I try with my setup, here is a video from youtube where they're using a similar setup to yours(a FireFace UFX and a Fender type guitar) :
If you notice the level at which he sets the input(input 4 in the video), it's about -13 to -12.
So, you could try what Matthias suggested to check that there is no problem with the BF Pro's input(which I don't think there is any), and if you 're not satisfied with the level, still, you could add a boost pedal or an overdrive pedal used as boost(gain 0, level max).
I use a Blackstar HT-Metal pedal(tube preamp/distortion pedal) with Impulse Responses, to record my guitar!
You could purchase a Fender MTG Distortion(more of an overdrive) to add some tube flavour to your tone! Or a Behringer VT-999 Vintage Monster(tube and also, a noise gate) as a more inexpensive solution(I use that one along with the Blackstar)!
Or any other pedal of that type, that you like!
EDIT: I forgot to suggest, that you should try your input, also with palm muting in the low strings, as the bass frequencies will increase the level as well !