Below are instructions on how to update the firmware on your Reverb. Attached are the firmware files and the changelog.
How to upgrade your Reverb's firmware
1) download the firmware file from below. It should have the format eervXXXX.bin where the XXXX is replaced by the version number.
2) copy the file to the root directory of a high-capacity SD card that's been formatted FAT32.
3) insert the SD card then power on the pedal.
4) The preset LEDs should marquee yellow for a bit, then all turn green when the update is complete.
5) remove sd card, cycle the pedal's power, and you're good!