I just bought my Riddex Plus repellent. So far, I'm satisfied. The red light blinks for 3 minutes, then it's off for 3 minutes. If the red light stops blinking, your Riddex isn't working. I read that in the instructions. So, the real test will be if I hear little critters in the soffit of my basement walls. I'm tired of being treated like a second-class citizen by my condo association. So, instead of getting angry and frustrated, I hope that Riddex will do the trick and I won't have to bother with my condo association anymore!