| 1337 Gamer said: its really uncommon. Take it back to the store and exchange it |
In all fairness, 360 problems are not uncommon. At the risk of being called a troll I'd even go so far as saying they are common. The op just thought the risk was worth whatever the 360 had to offer him in return, and he got a raw deal. Shit happens, life is pointless without any risks and all that wise oneliner blablabla.
Anyway, you said that normal av cables do provide a picture but no sound? That would exclude your gpu from being fried. This leaves but a few options. 1. broken hdmi port on your 360. 2. broken hdmi port on your Panasonic. 3. broken hdmi cable 4. wrong setting on either your TV or 360.
I suggest having a tech friend look at it asap and return the console on his advice. No matter how well meant advice on a forum is, it does not constitute someone looking at it in person.

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