Yes it does, but the first Duo X models have issues with playback.
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Okay, so I read https://wiki.moddevices.com/wiki/Audio_Through_USB and used the “USB Audio Gadget” mode to try to turn the Mod Duo X into an audio interface.
I realized that if I wanted to use it as a traditional Audio Interface, I have to route as the following:
Routing A: Hardware Capture 1, 2 into Hardware Usb Audio Playback 1, 2
Routing B: Hardware Audio Usb Capture 1, 2 to Hardware Playback 1, 2
After doing this, I tried recording some things on Logic Pro.
I found that the latency is quite bad, even though Logic says that it should be pretty good. I think I know why this is so and the following is my train of thought:
- There is a fixed latency when any audio signal is passed through Mod Duo X (about 8ms).
- Routing A adds 8ms to the latency.
- Ideally, what you would want is to “directly” hear the output of the computer (i.e. Hardware Audio Usb Capture 1, 2 directly into Hardware Playback 1, 2), but as is, there needs to be another virtual routing (Routing B), and this adds another 8ms to the latency.
- Logic only takes into account Routing A’s latency, since it doesn’t know that it takes an extra Routing B for the listener to hear, so it thinks the latency should only be 8ms.
- However, in actuality, this setup always results in doubled latency, 16ms + alpha for 128 frames async, which is quite noticable, especially with any additional processing on Logic.
So what I think is: since if you are using this device as an Audio Interface, you don’t actually need any processing inside of the Mod Device for either Routing A and/or Routing B. So maybe a “Bypass” option for Routing A and/or B would reduce latency significantly. Of course, I don’t know any inner workings and this might not be feasible at all, but since there is a condition that these Routings do not require any processing, maybe it is possible to reduce it?
Some of your assertions are not quite correct.
Adding a connection doesnt double the latency, the extra latency on the USB audio gadget comes from how it is setup at the moment.
It is too early to do tests on latency for this, as everything is still in preliminary phase. There is a double-double-buffering going on with the audio when sent over usb, which can be heavily reduced (we will do some tests for this later on)
And there is an amount of cpu usage/processing when enabling and using such feature. We do not have a dedicated chip/hw doing this, it is all in software.
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Hey there, I was trying the USB gadget method on my Mod Duo X and after rebooting, I can not access the unit anymore neither via ssh nor the Web Interface. I backed up my data so I don’t mind doing a manual update. However, since I carefully followed the steps in the wiki page, I was wondering if I’m missing something or if it just happened because this is still an experimental feature?
Also, any plans to make this an actual feature in the future?
Thanks 
Depends if you use Windows or not. For Windows a special extra file is needed, but I guess you followed that…
So, no idea.
The MIDI “gadget” mode is already enabled on the Dwarf, seems to work without issues. So it is likely we will bring this feature first to the other units.
The audio “gadget” is on the roadmap for the Dwarf too, but with a few things that take priority over it.
Something to see happening in 2022, just hard to say when exactly right now.
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Thanks ! I’m using MacOS and the process seems to go well all the way through the reboot. The problem is, since I cannot access the web gui, I don’t know if it worked or not 
I have been trying to make midi work connecting my Duo X Version 1.11.2.2676 to a MacBook Pro with Logic Pro 11 and/or Garage Band. I have had weird mixed results, but I am still missing something. I have a Alesis V61 keyboard; guitars and a bass. When the keyboard is connected directly to the computer, that works fine. When I connect the Mod Duo X to the computer as well, I can direct the sound back out of my computer into the Duo X and out to the PA. The sound coming from the computer also gets mixed with the pedals I have active on the Duo X. What I can seem to make happen is the sound(signal) from the Duo X to be sent to the computer. On the Midi Setup app, I have made an aggregate with EShare Audio (not even sure what that is but it has 6/6 in and out); MacBook Pro Speakers; DuoX Playback and DuoX Capture. On the DuoX, I have enabled Midi with the Sudo command and in the Midi Port list, I have tried all the different options, but currently have Enable Virtual Midi Loopback, and Aggregate mode checked. USB Gadget Midi 1 in/out isn’t selected, but it has made no difference when it has been selected.
I know it is just a matter of knowing how/what to do and admittedly I am pretty new at midi connections. But does anyone see what I might be missing or doing wrong? Is the DuoX still receive only?
Yes. From what I understand what you are doing wrong is that you are assuming that MIDI sends audio. That is not the case, MIDI sends…well MIDI. In other words, data. Not audio signals.
To send audio from the MOD DuoX to your computer, either you connect the audio outputs of the DuoX into the audio inputs of a soundcard connected to your computer (either the 2 outputs or the headphones output, although I would recommend you to use the first), either you use the SPDIF output of the MOD DuoX. For this last option, your soundcard should have a SPDIF input.
Nothing here is related to MIDI. Regarding MIDI, you can send MIDI from the MOD DuoX into your computer, load some virtual instrument on your computer or something controllable and play it from the computer.
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Is it possible to use an external USB Audio device like f.e. the Behringer UCA222 to add more input channels to the Mod Duo X?
I’d love to be able to add an extra input for a sidechain signal - the compressor plugins having a sidechain input isn’t very useful without being able to input a sidechain signal into the Mod Duo X :-/
Not yet. It’s been a request by many people including myself.
It’s on the development list as far as I know
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Duplicating from 1.12 firmware discussion, as this is probably more suitable place for this piece of knowledge.
- Usb audio gadget mode on MDX seems to cause USB connection fails, it was doing the same on 1.11, but at lower rate. Now in 1.12 probability of failed usb connect seem to raise up compared to 1.11, and it might take series of reboots to connect.
Try disabling audio gadget before blaming hardware, buying stacks of new USB cables, etc.
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Forgetting to create file that is responsible for windows compatibility caused complete USB connection disruption for me on windows, if audio gadget is enabled.
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I’ve just noticed that hardware UI in 1.12 has new menu for enabling audio gadget mode in my MDX : System → Device Settings → USB-B Mode setting. (UPD: only for midi, not audio)
Seems to me like it does the same stuff that was made be creating flag files via ssh/touch, but you can do it without USB connection, and therefore restore usb connectivity by disabling experimental feature, if something has gone wrong with audio gadget.
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correct, except we only enable MIDI with this, the audio part is never enabled as that needs more attention.
will give this issue some attention soon.
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Just wanted to check in to see if “native” USB audio for the Mod Duo X MDX is in the works?
I understand the Duo X is still on an antiquated kernel…
What do you mean with this question, “native” in which sense?
I mean, will it be an available feature? and is it in the roadmap?
Currently, it’s noted above that it’s not production-worthy in terms of stability, let alone latency.
I understand 2022 was tumultuous for MOD… Any hope for USB Audio being a stable feature for MDX in '23? 
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I was successfully sending audio back and forth between my Duo X and my computer (Mac) using the USB-B socket.
I then tried hooking up another device (A&H Xone 96) using the USB-A socket and got nothing. Note that USB-B was unplugged at this point.
I then tried with my computer using USB-B while the other device was still connected to USB-A and got no audio.
So the only case this seems to work on the Duo X is when only plugging a cable into USB-B.
Is this confirmed? Expected?
The DuoX acting as a usb-soundcard is not the same as the DuoX hosting a usb-soundcard.
So I’d say: yes this is expected, you are only using the DuoX as a soundcard itself (which works completely differently from it hosting a separate device).
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Right, that makes sense that you cannot connect two ”devices” without a ”host”. I guess I never considered the various USB ports to indicate host/device. But I get that one of the things you connect needs to set the sample rate used etc.
But I’m not sure I consider any of the devices in my setup a soundcard. So would it make sense for the Mod devices to not be soundcards sometimes?
I’m basically looking for the Duo X to replace a computer in a live setup. And being able to host devices would make it better at that.