My name is Eric
I have read your issue and here is what it sounds like:
It could be just a few bad capacitors on the power supply, if you want to attempt the repair yourself you can do a visual of the power board, caps may appear swollen on top
The ones you are looking for are located almost center bottom of the power board, I can see them clearly with the back on simply shining a flashlight into the back through the holes.
With the back removed you will see a few circuit boards the upper one (ac cord runs to it through the ac socket) is the power supply, it has alot of capacitors on it (cylindrical standing straight up soldered in mark on the sides with the positive/negative sides and MF and Volts values)
Philips uses 2200Mfd or 3300mfd at 35Volts rating capacitors, they cost about $1-$2 each here
usually I replace two of them (or all the bulged on top ones) .
The power board and back unscrew with a torx bit and screwdriver, if you do not know how to desolder and resolder then do not attempt this as you may damage the TV more than fix it.
We do not recommend do it yourself, but depending on your knowledge and technical ability you may be able to.
You can replace the whole power supply, but Philips has a few versions in their sets and some won't fit due to cable location (sockets) being in a different spot.
If there is a blinking red light on the TV count the blinks, 7 blinks would indicate a bad buffer board , check the capacitors by looking for the swollen tops I hope thats all it is (usually is)
here is Philips Phone # 1-888-744-5477 in case you need it.
hope this helps