Microphone.activityLevel causes strange crash


I’m facing a really strange problem. I’m running a timer event which contains Microphone.activityLevel. Like this:

var level:Number = _mic.activityLevel;

level -variable controls embedded movieclip. Everything works out fine until suddenly Flash Player crashes: processor usage jumps to 100% and animation freezes. I first tought its after 30 min but now it seems there is no clear pattern: it’s usually somewhere between 30 - 120 min when it happens. Same thing in browser and stand alone. I have newest version of player.

I also tracked down the bug to Microphone.activityLevel, because if I put

var level:Number = Math.random() * 100;

instead, everything works out fine.

I have Mac OS X 10.5.6. and I haven’t got opportunity to test this on Windows yet.

Could someone explain what causes this?