Pioneer Mixer to iPhone Audio Setup

I'm looking for an expert to help me achieve perfect audio from my Pioneer mixer to my iPhone for live streaming using a USB interface.

Key Requirements:
- Connect Pioneer mixer to iPhone via USB interface
- Ensure high-quality, professional-grade audio output for live streaming
- Troubleshoot and optimize audio settings as needed

Ideal Skills & Experience:
- Experience with Pioneer mixers and iPhone audio setups
- Strong knowledge of USB audio interfaces
- Background in audio engineering or live streaming setups

Please share your relevant experience and approach to this task.