Turn off internal speakers

Did you check on YouTube ?

These blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices. http://electronicshelponline.blogspot.com/
Blinking codes details to many popular brand TVs are given. Surf the site with patience.
If blinks continue without any pause, the main board is faulty.

There is usually a location somewhere in you customer menu where you can turn the internal speakers off.
Page 34 of the owners manual.... http://service.us.panasonic.com/OPERMANPDF/TCP42G10.pdf shows "speakers" you should be able to turn them off & on there.

Might be a problem with bulged capacitors - its one of the most common faults on any electrical item - best take it to an electrical repair shop.

Unusual on a Panasonic television as they are the best you can buy for a reason they used to use the best capacitors and internals.

Go into menu of the TV and go to the setup for sound and pich internal speakers.

Pan has an ECO feature that automatically turns tv off if no buttons pushed for 3 hours. Check Menu to make sure this feature is turned off.

Feed the audio from the google tv to your panasonic tv then the audio from your tv to your amp

Please check in the Menu under Audio section if you can disable the internal speakers. In the Sony and Samsung TV's you can. It will be in the bottom of the of the audio scroll Menu.
It will ask you TV sound Internal / External ?
Choose internal

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