How do I stop the 3g/4g radio from turning off? When I watch youtube videos on my samsung epic 4g, most of the time when I click a video to watch it does the "Loading" spin gif animation forever, and I can see the little arrows on the 3g/4g symbol are off.

If I hit back and load again 3 - 5 times the arrows light up and the video acutally plays.

This is incredibly irritating. 

Is there a way I can tell the phone to always keep the radio connection active while the charger is plugging in, or something like that?

Alternatively, does anyone know how if there is another way to fix this youtube issue?

Thanks so much, this is driving me crazy.
If you see the 3G/4G symbol and the arrows are just grey, that just means that you have data connectivity but there is no send or receive activity at the moment.

I guess you made an false assumption: The data radio is only off (deactivated) if you don't see the the symbol at all. Otherwise, if the symbol is there and the arrows are grey, your radio is on, but there is no traffic happening at the moment.