what you'll need: Same as DMG Maxi, MIX 2.x firmware family. USB-A to Micro-USB + Windows PC (DFUSec), or myMIX app Bluetooth OTA.
1Same procedure as DMG Maxi. Download MIX-CT-FLASHING-BANKS-V2.1.3.zip from https://us.rosco.com/sites/default/files/content/resource/2023-03/MIX-CT-FLASHING-BANKS-V2.1.3.zip
2Install driver via lct_installer_1.exe if first time on this PC.
3Launch DFUSec.exe, go to File > untick 'Lock LINK2 function'.
4Connect MIX controller via Micro-USB, power off first.
5Enter update mode: hold red dimmer button, power on controller, release dimmer but hold ON/OFF.
6Click Start in DFUSec; wait for both flashing steps to complete.
7Power cycle and verify firmware version.
GotchaMAXI MIX is an older marketing name for the DMG MAXI / Rosco DMG MAXI, same hardware and firmware.