My KF-42WE610 does not like to turn on

Hello, my Sony KF-42WE610 does not like to turn on. I had the lamp replaced in August and about three months later this new problem started. It come and goes in spells. I'll turn on the power and the green light flashes and there is a sound that comes and goes (it sounds like a CD player winding up), then after a few minutes, the red lamp light will flash. After pressing the power button on and off the TV will start up and work fine. Some times I just have to turn the TV on and off three times, and other times it will take three hours of pressing the on and off button to turn on the TV. Some other times this will not happen for a week at a time. I have reinstalled the lamp and tried other little thing. Any help, any one know what part I need to have replaced? Any help please.
Thanks,
August