switch the position of mind freeze and strangulate.... it works that way because strangulate is an instant cast from ranged, hence why it fires first, you have to be in melee range and have frost rune for mind freeze... essentially you get strangulate always working if its up, and mindfreeze working when strangulate is on cd... there is no other way to do it, unless you use a modifier or perhaps there's a way to check for range in macro before firing... tho i dont know

i usually prefer it to cast strangulate first anyway, because you can use it to pull casters in pve, or hit a mage in pvp before they can frost nova, then you should be able to beatstick them through the silence before they know how to react lol



good luck!