So I bought my Salsa a couple weeks ago and I'm pretty impressed with it.

One thing I've noticed it that when I apply the right amount of pressure or have it at certain angles that the noise level changes abruptly and it gets a louder rattle or buzzing and it's a little distracting.
I think it's the motor rattling against the plastic shell and I've had cheap plastic vibes make a similar noise.

I've been looking through the forums and reviews for the Salsa, but no one's really mentioning this. I'm not sure if this is normal for the Salsa or if it's a sign something's not right and could get worse over time.