When playing around with my friend on his Shaman, I was dueling him on my Affliction lock. I put UA on him just before he was able to drop his grounding totem. When he dispelled the UA effect, the silence reflected off the grounding totem and silenced me instead. For the grounding totem to reflect, you need the glyph for it.
Basically, before you decide to dispel UA, please a grounding totem and then dispel to silence the warlock.