Mackie V3 mixers USB drivers issues

For its most recent series of USB mixers, the V3 series, Mackie has written and provided a proprietary Windows USB driver (for the first time) which supports a pair of stereo USB channels; Mackie has named channel one ProFX 1-2 and channel two ProFX 3-4.
When installed in Windows and with the mixer (in my case a ProFX10V3) powered, Windows (clicking on the tray speaker icon) will show both of these names available for use depending on which mixer input lines are being used and plugged into. The default Master out and Control Room outs are connected to channel ProFX 1-2 with the second ProFX 3-4 pair connected to a switchable mixer stereo input line 9/10.
When running the new version of Audacity, v 3.2.4, and trying to choose Audio Setup->Recording, only ProFX base driver (called simply ProFX) is shown along with ProFX 1-2 Loopback, and ProFX 3-4 Loopback but not the non Loopback plain ProFX 1-2. The ProFX 1-2 Loopback isn’t suitable for recording because of the infinite feedback produced. Interestingly Audio Setup->Playback selections DO show the plain ProFX 1-2 channel and the ProFX 3-4 channel which are the ones I need to have access to.
Obviously these new Mackie proprietary USB drivers confuse Audacity, by what is being delivered by the Windows audio system perhaps (?)
BTW up to now and with the old Mackie V2 mixers only the built-in Windows compliant USB drivers were used so I never experienced this issue before. Also the these newer Mackie V3 mixers must have the Mackie USB drivers installed, they don’t work as USB mixers with only the default Windows USB drivers.
Is anyone else running the newer Mackie V3 mixers with their proprietary USB driver interfaces and how did you solve this problem ?
-Thanks in advance.

I don’t have experience with the Mackie V3 mixers, but I have had to deal with a lot of oddball driver issues and there’s a “trick” that sometimes works when all else fails:

The bottom line
Release builds of Audacity for Windows can only use drivers that are fully supported by the Windows sound system. Drivers that bypass the Windows sound system (namely “ASIO” drivers), or any drivers that are not fully supported by the Windows sound system are not supported by release builds of Audacity. (It is “possible” to build Audacity from the source code with ASIO support, but only for personal use, due to licensing restrictions. https://manual.audacityteam.org/man/asio_audio_interface.html)

So the “trick” is, that if the driver is fully supported by the Windows sound system, then you can configure the Windows sound system to use that driver by default. Audacity can then be configured to use “Microsoft Sound Mapper”. The Sound Mapper is a “virtual device” that sits between applications (such as Audacity) and the default (real) device drivers. This way, interfacing with the device driver is handed over to Windows. If this is set up correctly but still does not work, it’s because the device drivers are not fully supported by the Windows sound system.

On the surface, this appears to be an enigma. The reason is because other mixers have a USB 1/2 input supplying channels 1 and 2 (or the main mix) and a USB 3/4 input supplying channels 3 and 4.

I don’t have a ProFX10v3, but here is my take after reviewing the available online documentation:

Not necessarily. However, mixer settings are complicated and in some cases extremely confusing. Let me suggest downloading their MP4 video here: Drivers/Downloads | MACKIE which may help clarify the situation.

Yes, so this is because the ProFX 1-2 and ProFX 3-4 are outputs NOT inputs. And since most outputs are available as loopbacks, you have the the ProFX 1-2 (loopback) and ProFX 3-4 (loopback) available as loopbacks. The only real input provided by Mackie is their “Main Output” or ProFX base driver (called simply ProFX).

The only USB INPUT available to Audacity is the mixer’s MAIN OUTPUT (pre-fader). The Main Output (pre-fader) and the USB input will always be identical unless the “Break” switch is used to mute the main output. There is NO option in the mixer for the software to monitor any channel directly.

The ProFX 1-2 USB OUTPUT is mixed with the Mixer Direct Monitor Bus and when selected by pressing the “To Phones/Control Room” switch, is output to the meters, headphones, and control room. This is used for overdubbing.

The ProFX 3-4 USB OUTPUT is input into the Mixer channel 9-10, which defaults to the 1/8" input unless the 3/4 switch is down. This is used to allow the the computer play music though the mixer.

Note that Audacity is not capable of producing more than one stereo output at a time.

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To summarize, there is one stereo USB input from the mixer’s “Main Output”, and two stereo outputs (1-2) going to the headphones and (3-4) going to channels 9-10.

The limitations above are integral to the mixer hardware and the options remain consistent regardless of whether you use MME, DirectSound, WASAPI, ASIO, MacOS, or Linux.