A few questions, as I'm not playing a Shaman and assumed this already works:
1) what's the EXACT spellname you're using to clean, including rank?
2) what's the EXACT debuff name on the person that is MCd?
3) which border color does that debuff have?
4) which wow client language are you using?
Don't play a Shaman either, but if this helps:
1) Purge - both Rank 1 and Rank 2 have the same mana cost, so I'd think Shaman would just use Rank 2 all the time.
2) Dominate Mind
3) It's a Magic Debuff, sorry don't use the default blizz frames and I've never seen the border color. Aren't Magic Debuffs blue, though?
4) This is with enUS client.
yep fits besides 4) using enGB here. And for 1) yes, I use Purge(Rank 1)
Would be nice if you could put it in, thanks.