I have a 2006 FWD Escape Hybrid. Lately, I've been hearing a weird sound coming from the back of the car. It sounds like a drip of water falling into a full sink or maybe an owl far away in the night. Like whirrrrrup or hoooooooooooohoo. Has anyone heard this or have any idea what it could be? It seems to happen when going around curves and accelerating at the same time...but I cant really predict it.