Of course.
I’m sure it’s down to how the recording device / app handles the input settings. In general, if you have recording issues manually syncing input and output settings between devices might resolve it.
On windows, it seems that part of the problem comes from a lack of access rights for the system audio settings but I haven’t been able to confirm that yet - trying some of the settings I listed in Audacity first didn’t resolve my previous issues, but it did on a system level.
I received the mentioned Error 9999 as well during my testing but only when forcing the default audio devices in the system settings to any of the mixer inputs without the prior frequency sync. I later discovered that setting the default audio device isn’t necessary since the communication problems only seem to revolve around sampling rate, channels and frequency.
Maybe there’s a way, with the X1800 Prime Panel software, to further “force sync”/override those variables for the multichannel input device so this manual step wouldn’t be necessary?