gnome-mines crashes frequently

Mines crashes quite frequently, when it does it usually crashes when clicking on a mine.
Also the game sometimes reacts to clicks very slowly, as if it was lagging... If I restart it works normally again.

Crash:
":~$ gnome-mines
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 14: Having multiple values in <test> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Fontconfig warning: "/etc/fonts/conf.d/65-ttf-sil-andika.conf", line 32: Having multiple <family> in <alias> isn't supported and may not work as expected
Speicherzugriffsfehler (Speicherabzug geschrieben)"

Last line means: Memory Dump

gnome-mines 3.8.0
Ubuntu 13.04