I picked up the Digigram VX222e because I wanted to show off an audio interface with open-source drivers and official support for Linux. Instead I found myself googling whether or not dumpster-fire was hyphenated.
Drivers
VX222e boards with hardware revision IS=06 or higher require the latest pcxhr driver from the Digigram Github Repo. Earlier hardware revisions can use the snd-pcxhr driver included in the Linux kernel.
Alsa
You can control the VX222e directly with alsamixer.
Pulseaudio
The Digigram VX222e performs like any other sound device with pavucontrol.
Jack
In order to get usable audio from the VX222e with Jack2 the Period/Buffer needed to be set to 8. Anything lower would result in distorted audio or the VX222e failing to initialize.
Round-trip Latency
While many kinds of audio latency metrics exist, one useful and well-understood metric is round-trip latency; the time it takes for an audio signal to enter the input of a device, get processed, and exit the output.
Testing setup
| CPU | AMD Ryzen 7 1700 |
| RAM | Corsair Vengeance LPX 16GB |
| Motherboard | MSI B350 Tomahawk |
| GPU | Nvidia NVS 300 |
| SSD | Samsung 840 |
| PSU: | EVGA 600 B1 |
| Firewire: | Syba SY-PEX30016 |
| Network: | Intel i350-T4 |
| OS: | Debian Bullseye |
| Kernel: | 5.16 low-latency |
| Desktop: | NA |
Verdict
The VX222e functions as a 2 in / 2 out sound card and that’s about it. I was unable to access the 3-band parametric equalizer or maximizer under Linux. The high round-trip latency with Jack makes the VX222e unusable for live monitoring post effects.
If your looking for a Linux compatible interface that can handle AES check out the MOTU 8D.
Digigram VX222e
The VX222e from Digigram is a PCIe (Express) card that provides 2 channels of analog or digital audio input, while simultaneously outputting a stereo digital output or 2 mono channels of analog audio.
Pros
Functions as a 2 in /2 out sound card.
Analog + AES I/O.
Headphone jack.
Open-source drivers.
Works with Jack, kinda.
Cons
PCIe bridge.
EQ and Maximizer effects are not accessible under Linux.
High round-trip latency.
