We recently purchased a house with our first inground pool. It has a Jandy G12 Fiber Optic Pool light with three outlets inside the pool. The Metal Halide Bulb shuts off after about 3 min. After about 5 min the light bulb comes back on. I have a feeling the bulb is not getting as bright as it should since you can barely see the light at the outlets in the pool. Please help. Is it the ballast? Starter? other?