diff --git a/mk/linux/glestkeys.ini b/mk/linux/glestkeys.ini
index 7e087557..694ca326 100644
--- a/mk/linux/glestkeys.ini
+++ b/mk/linux/glestkeys.ini
@@ -11,8 +11,8 @@ CameraModeUp=vkUp
 CameraModeDown=vkDown
 PauseGame=P
 ChangeFontColor=C
-GameSpeedIncrease=vkAdd
-GameSpeedDecrease=vkSubtract
+GameSpeedIncrease='+'
+GameSpeedDecrease='-'
 ExitKey=vkEscape
 GroupUnitsKey1='0'
 GroupUnitsKey2='1'