I have a problem with my TK41's power (right-side) switch. Sometimes when I press to turn ON nothing happens. Other times when it does turn ON, it does not turn OFF when I want to turn it OFF! The MODE (left side) switch seems to cycle ok. There are ever times when it goes to strobe when pressed for LOW-MED-HIGH. The light is two months old, seldom used, on its first batch of new first-time charged Imedion 2400 mAh cells. What is the problem? I hope you guys can come to the rescue!