The unit I received may have been defective. A replacement is on the way so I'll find out soon and let you know if a new one solves the problem. But on the first, I drained brand new batteries in less than two days, even when turned off. My old device that I had for years could use the same batteries for months. Update: The replacement I received doesn't eat batteries. I sincerely hope they actually heard why I returned the product and not just repackaged it and sent it back to another unsuspecting buyer. It was really a guy but the new one works fine and doesn't kill batteries. Must be a defective electrical component. I've increased my rating from 2 stars to 4 stars. For the price it would be 5 if the first block wasn't defective.