Don't know if anyone else is experiencing this but me, but here it goes..
I'm playing Trauma Center: Under the Knife - USA, I fold the DS up to put it in sleep mode, and all of a sudden, the screens flash, and the green LED light also flashes rapidly, the DS itself makes small noises (even with volume turned off), like the noise you hear when you turn off the DS. I don't know if it does this with other games or not, since this is the only game I have tried 0.6 B2 on so far.