I've tried to get this working in the past with no success, so I'm hoping the wisdom of this forum may come to my rescue.

Use case: single channel, phantom-powered mic for voice-over recording. As simple as it gets.

Gear:
Sennheiser 416 mic into...
  ...Grace Audio m101 pre-amp into
     ... Line In 3 of RME Babyface Pro into
        ... iPad Air 4
            ... need recommendation for a clean, compatible recording app that doesn't color the audio

Config:
- I first made sure the Babyface Pro's firmware was up to date. Then I followed the videos and KB articles to get the Babyface Pro into class-compliant mode. I installed the TotalMix Pro iPad app and tried to use any one of maybe 5 different recording apps including Garageband, but I could never get any of them to register the output from the Babyface Pro.

I normally have this working fine via my Windows 10 computer via the USB interface. I just can't get it to work via an iPad instead. I'm certain it's just user error somewhere, but I can't find detailed enough instructions anywhere.

If there's paid support options to help step through this, let me know, as I'd happily pay for experienced help.

Any tips, tricks, or detailed how-to guides out there would be appreciated.

Thanks in advance.