Files with digi file suffix are related to the DIGIBooster module format.
DIGI file extension - DIGIBooster module format
What is digi file? How to open digi files?
File type specification:
The digi file extension is associated with the DIGIBooster, a music composing software also known as tracker, developed for AmigaOS 3, AmigaOS 4 and MorphOS.
The digi file stores sound module from DIGIBooster.