To upgrade firmware (from v10 on) you can use OwlControl, and the process is now easier than ever. It’s all done over USB MIDI and no additional drivers are needed.
Simply download the appropriate syx file from GitHub [1], then in OwlControl go to Tools / Update OWL Firmware and select the downloaded file.
To ensure that the firmware is valid we use a checksum, which has to be copied from the release information.
If you enter the wrong checksum, the pedal will signal an error. However this error is not flagged up in OwlControl and easy to miss.
See the screenshot: the software says Firmware Upgraded, but it has actually failed and there’s an error message below the Remote Control button.
We will resolve this in the next version of OwlControl, but for now please double check you put the right checksum in!