In the back of my TV, a violet brilliant light and a fan in the same area makes so much noise when I turn it on,I have the obligation to send this T V in a shop for a technician to fix it .Unfortunately,after changing the light and the fan ,it still making the big noise that always makes it impossible to use.The technician and I don't know what to do now.Can you tell me please what is the cause and what to do to solve or fix finally this problem? Thank you very much! VS