Not sure if I have a problem with mine or if the behavior is normal. When I first got the x2 each time I plugged it in, the blue led would turn on immediately. I normally plugged it in after 2 days of use. Now it hardly ever turns on when I plug it in (the light under the cap). The battery doesnt seem to be lasting as long either and I wonder if it is charging at all. I have tried different cables and plugging into several different usb 2.0 devices as well as 2 different VOLT wall chargers. Sometimes the light comes on, sometimes nothing. Other times it will sit for awhile maybe 10-15 minutes then suddenly come on? I will plug it in for the night and leave it and although I rarely see the light turn on, it seems to charge? Other times it will turn on immediately, charge for a half hour then off and tend to die very quickly under light use. Other times it will charge for several hours and last 2-3 days of use. Should I be draining the battery down fully until it flashes on the button? Is there some sort of "smart charger" technology built in where it won't top off a half or 3/4 charged battery? Time for a warranty return?