I have a bathroom wall fluorescent light fixture with 2-30FT12/CW/RS lamps. The fixture is about 10 years old and I love it, when it starts properly. About 5 years ago I had to turn it off and on a few times to get it on so I replaced the ballast and lamps. About a year ago the same thing happened and I worry that it may quit permanently. How do I know if it is the ballast or lamps? If it is the ballast do I replace it with Electronic or Electromagnetic? If it is the ballast do I replace it with Instant Start or Rapid Start?