Not the second time.
The car had been sitting for about 1.5 hours before I went back out and it was dead.
I have a 2002 bonneville that had the same problem right after i put my system in,
it turned out to be a loose ground connection under my back seat on the passenger side
i figured it out after two AAA calls and a shop couldn't figure it out.
when my car would die, my amp would just stay on even though i couldn't start the car
and everything was hooked up the right way.
you might want to check your connections and make sure they are not loose or anything