I have connected the Digirig to my ft-891 and my PI. WSJT-x seems to not know what audio divide to use and neither do I. I list from lsusb. CAT control is OK.
pi@radiopi:~ $ sudo lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 007: ID 10c4:ea70 Cygnal Integrated Products, Inc. CP210x UART Bridge
Bus 001 Device 005: ID 0781:5583 SanDisk Corp. Ultra Fit
Bus 001 Device 008: ID 10c4:ea60 Cygnal Integrated Products, Inc. CP2102/CP2109 UART Bridge Controller [CP210x family]
Bus 001 Device 006: ID 0d8c:013c C-Media Electronics, Inc. CM108 Audio Controller
Bus 001 Device 004: ID 0424:2412 Standard Microsystems Corp.
Bus 001 Device 003: ID 1546:01a7 U-Blox AG [u-blox 7]
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
pi@radiopi:~ $