Nitecore SRT7 blinks?

I have purchased my 3rd SRT7s. Instruction manual states that it will blink once in every two seconds when power level is down to 50%. All of mine does that with fully recharged batteries. No big deal but it does not function according to the manual. Do I have defective lights or I am not doing something right?

what kind of cells are you using? I know both my SRT6 and 7 blink on fresh CR123s as the sensor is only picking up 3 volts as opposed to 6 its just a huge misstep on Nitecores part. I use 16340's in both my 6 and 7 for max output. But barring that take some rubbing alcohol and a q-tip and clean all the contact points tail, tube and head and even the battery cell itself. My Srt6 did the same thing till I figured out that it was just plain dirty contacts now it works fine. I have yet to see any flashlight that didnt need a cleaning from the factory....

Thanks for the tip. I have cleaned it up as you suggested and it functions now as it supposed to. I will have to make it a habit to degrease all contact points on all of the new purchases.