I've tried uploading the firmware on my Marshall Code 25 using the Chrome, Opera and Edge latest browser versions on my Macbook pro 12.3 (Monterey) using a midi usb cable.
When doing the update the amp connects and allows me to click update... it shows the progress to 100% but then gives the error below:
"An error occurred. The update process was not completed. Please try restarting your computer/device, and then try the update process again."
I must have tried this a 100 times with no success.
Now when i resart my amp to play some tunes the display says "CHK USB" and the amp wont work.
This is all very frustrating and i hope someone can assist.
Please try the below to see if this helps ,
MIDI troubleshooting tips:
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