Skeptikos

What would you call that sound that someone makes on the phone when they don't believe what you just told them? It's a cross between a short laugh, like huh, and an aspirated sound at the same time. "I'm sorry I won't be able to come in to work today I don't feel well"."Huh. Well thanks for calling." Like they can't wait to hang up because they don't want to hear anything else you might have to say. I heard that sound today.