Important notice regarding v1.9.1 update for Duo users

v1.9.1 update for Duo users

Hello everyone.

The 1.9.1 software release is out and brings great new features to your MOD Duo. Not only it brings new features but it also allows users to migrate to mainline Linux, a newer cutting edge O.S. kernel that will make the units run more smoothly and reliably.

If you want to know more about Mainline Linux, please read this post by our CEO.

The migration itself is not a hassle-free procedure and shall be performed carefully. This blog post is meant to explain to our users the necessary steps for safe migration.

If you want to know more about the features included in the 1.9.1 release, please read this other blog post: MOD Firmware Update v1.9.

Now we need to bring attention to a special situation in regards to the next update for Duo units.

In short, we want to make the Duo more reliable and future proof but this involves deleting and recreating the entire flash data, so a manual step for existing Duo units is needed.

NOTE: Only needed for Duo NAND units! 

v1.9.1 Update for MOD Duo


The Duo on the left, without the laser engraving, is a NAND based unit. The Duo on the right, featuring the “logo + MOD Duo” laser engraving is an eMMC based unit.

All Duo users can update to v1.9.1 regardless, but only eMMC-type units get the new kernel automatically.

For details about what this new update provides, please see the v1.9.1 release announcement.

It is quite important that Duo users do the update procedure, as future releases will use the filesystem a lot (for the file handling feature).

This means that, going forward, we do not need to leave the Duo on the side (in terms of support) because new features can’t work due to using an old Linux kernel on the system.

In fact, as of today, the Duo is the one with the most up-to-date Linux kernel in all of the MOD products.


So now, how to update?

Again, note that this procedure will fully reset the unit to “factory” defaults, so backup your data first (can be done through the advanced settings on the web interface) if you would like to keep your current settings.


Special update image

The first and easiest way to do the update, is via a special update image.

(Please do not power off your unit once the procedure has started!)

To begin:

  • Turn off your MOD
  • While holding the left footswitch and encoder/knob down, power on the unit
  • Connect the MOD to your PC if not done yet and wait for a new mass storage drive to appear (LEDs will turn blue)
  • Download this special update file modduo-convert-nand_20200529.tar
  • Copy the tar file onto the new drive and use your OS option to safely remove the drive
  • Remove the USB cable connecting your PC to the MOD
  • Wait until the unit boots itself again in restore mode, indicated by the blue LEDs (this might take a few minutes)
  • Download the factory update file modduo-v1.9.1.1464.tar
  • Copy the tar file onto the new drive and use your OS option to safely remove the drive, just like before
  • Wait until the MOD sets leds green and then reboots itself (this will take around 5 minutes)

This is all you need to know to accomplish the procedure successfully. If you would like to understand it in-depth, take a look at our wiki


Manual deploy from FEL

We can flash the unit via USB in “FEL” mode, which will work regardless of the state of the unit.

We have a command-line interface setup for Linux and macOS users, and a LiveSuit image for Windows.

See our wiki pages MOD_Duo_Factory_Reset and Reinstall_via_LiveSuit respectively.

Let us know if you have any questions sending an email to 

We are here to help you throughout the way.