I am thinking its the push button on/off thing on the light. I have unattached it and looking at it now. In the meantime do you think this light is worth buying 240 Lumen Q5 Cycling LED Front Head Flash Light Torch Lamp Bike Bicycle Mount | eBay ? I also looked at an australia website called cyclingdeals.com.au but wasnt that impressed as really i am not going to go to $60 for a light