That is the exact one I have, with the PCM4202 and PCM1798 ADC and DAC. I have connected the SPI after having soldered the headers onto the core board. I then am using the USBi to change the values.
This allowed for the temporary download to the device, but not the permanent change to the software, which is a problem for persistent change of what it is running. No one wants to have to apply the download each time you turn the device on and off. So to address that, you have to generate an LDR file, then after that set the boot of it.
I’m currently running into memory errors in my compiling of the schematic I made, so I will attempt to reduce the schematic size hoping that is the issue and not something else. I am not a coder, but can recognize patterns at a great rate (how I learn). I have made the changes recommended in the document, so I have to finish making the application for incorporation of the LDR, then I will look at doing the other parts to be incorporated into the LDR. Then after that comes the flash.
Unfortunately, I have no idea who the manufacturer was on these.
Did you get the software to at least use the program that comes with it? The USB midi program and the IIR filtering showed in the ad?