The github version has a patch not present in released version.
The crash is explained in
https://github.com/milkytracker/MilkyTracker/issues/320
- Bug#1051256: milkytracker crashes with signal 6... Yves Le Berre
- Bug#1051256: milkytracker crashes with sig... Yves Le Berre
- Processed: Re: milkytracker crashes with s... Debian Bug Tracking System
- Bug#1051256: marked as done (milkytracker ... Debian Bug Tracking System

