Does she sing at all?
I'm curious if anyone would know, but I've just seen a few references to her 'beautiful singing voice' but in My Little Pony they give the 'singing voices' for the characters decent billing and all of her songs are performed by another voice actress named Rebecca Schoichet. (Who sounds a lot like the singing voice of Princess Clara, but none is credited on IMDb)
I was just a little curious - I know that the fact she has a singing voice actress in that show doesn't mean she can't. In the Disney film Mulan Donny Osmond sung the parts for the character Shang even though that actor could also sing because they felt Osmond's singing voice sounded more natural for the character..
I suspect the problem is that you have too many paperclips up your nose