The problem is probably caused by a power supply fault.
Finding the cause of the malfunction of switching power supply of television can be sometimes tricky, because a short circuit or over-consumption at any stage of the team, could cause the power supply does not work or do poorly (low voltage , ringing, etc.).
You should verify that the power supply is working properly, delivering the proper voltage, it indicates that the cause of the problem is in another circuit TV (or monitor) and not at the power supply.
Also the fault can be caused by a vertical circuit problem.
To solve this problem you can call a local TV repair shop for an idea of what is going on and what it would cost to repair.
Here you are a technician service website: www.tvrepairjacksonvillefl.com
leo
August 2012