A USB Mixer that appears on paper to be ideal to purpose with BIAB is the Yamaha AG series of USB Mixers. The entry level mixer is in line with the OP's budget and head to head comparison to both Focusrite and Sterling, is an equal value to either. Particularly with routing, pre-amp quality and monitoring. It's DSP software has reverb, compression and amp modeling. USB-C connection @ 24/192 It has more versatile input options and it's loopback feature should receive BIAB stereo Mix directly as I interpret the documentation.

Yamaha AG06 Mk2 6-Channel USB Mixer

EDIT: From the original post, "What audio creation soundcard / interface would BIAB users currently recommend as I am looking to buy BIAB 2024 and, like all of you, will be looking for the best possible sound output. Either an internal or USB soundcard is acceptable. "

The Yamaha AG06 is a viable option to recommend for use as an interface to BIAB/RB providing equal recording capability, more outputs, more inputs, DSP and direct steaming from BIAB it appears and is an option within the proposed budget. Yamaha provides it's own ASIO drivers that should make installation and integration with BIAB without issue. I'm presenting this as a recommendation that's hopefully not off-topic.

Last edited by Charlie Fogle; 03/29/24 06:09 AM.
BIAB Ultra Pak+ 2024:RB 2024, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.