I just purchased a light and when turned on, makes a high pitched whining noise. The noise will change a bit when changing brightness modes, and will go away when I put the light in turbo. It is a small light made by Kodiak that I got from Walmart. Should I be concerned about this and get it exchanged? It was only $20.00, but I would hate for it to fail due to a defect a day after my return window comes and goes!