We lost power and our insignia 47 inch will come on but there is no sound or picture, and the power button blinks about 15 times then stops... any suggestions?

dear it seems that the pcb got problem

That is most likely a bad diode in the power supply. It will require repair but it should be reasonable. There are youtube videos showing the repair if you are handy.

Im not 100% that this is the cause, but it seems like it

These flashes are fault indications, and are called blinking codes. By the number of flashes occur at one time switch ON, you can get an idea about the faulty circuit stage inside it. If you wish to get more details, check the site linked here
http://electronicshelponline.blogspot.com/
Selecting the view option, either to Mosaic / Time slide, can be selected by the drop-down list, at the top left of the display window, will make surf easy. You can also do a search, by type in the brand name/model number/IC used, in the search box at the top right of the display window.

The blinking light codes can be found at this website.http://www.agoraquest.com/viewtopic.php?forum=70&topic=31721

unplug it and hold the power button for ten seconds then release and plug your tv back up it resets it and should fix your problem

how many times does it blink between pauses as it may be a error code

It is symptom of weak Lamp in your TV, replace Lamp with following part number..
A1606034B LAMP BLOCK XL-2100U
It is available in Sony Accessories for $200
Always buy Sony Original Lamp for your Sony TV and avoid aftermarket/ cheap lamps.

i have a model #pt-53wx42f when you first turn the t.v. on it gets shakey and distorted then it shuts down and the power button light starts flashing

I have the sames t.v you have to go in the back flip the power cord switch...then reboot the t.v.

sounds like you lost ur power supply