Hello!
What do you mean by "refresh"? Do you have the firmware file and just want to rewrite it? I guess not ...
For the flashing operation you'll need:
- the Atmel Flip application:
https://www.microchip.com/en-us/development-tool/flip
- a special USB cable (Type A at the PC end and a smaller connector at the SOtM switch .. in the picture above, look at the right side above "SEL1" text and below those 4 resistors there is a 4-pin connector)
For the firmware you need to contact SOtM (May is great at customer support:
may.park@sotm-audio.com) and provide them the serial number located under that clock board. They charged me $100 for this operation. Optionally they can send you also the USB cable, clock IN connector and cable for some extra $.
Hope it helps,
Valentin