Death Sound not playing for imported models

[missfairy]

I've noticed something pretty strange. When I use a imported model the death sound effect for that unit doesn't play. (I know the unit has one since when using the default model the sound plays properly, but when I go back to my imported it doesn't)
Does anyone know what the source of this problem is and if it can be fixed? Thanks.

Also, please note all the other sounds seem to play properly. Such as the weapon hitsounds and the character speaking when selected, ect. Which is part of why this issue has me so stumped. =S