What the heck is wrong with this Blackberry thing?

[Aguiluz]

Just a few minutes ago, I heard a very very extremely high pitched whistling sound that seemed to just drill into my skull. It wasn't very audible or loud, but sure it was annoying as Heck. First, I checked the alarms for Monoxide and the Smoke alarm. Nothing. Then I checked the air filters, my PS3, monitor, laptop, nothing.

Then I followed the high pitched noise and my ears led me up to this:

It was charging my Blackberry, and when the battery went 100%, the little wall-wart would start making this annoying infuriating high pitched noise. I confirmed that it was the source of this noise as plucking it from the wall caused an immediate stoppage of the noise.

So what the heck is wrong with this thing? Is it caused by some defect and I would need to make a warranty claim?

 

[robm]

Hmmm... yeah, definitely warranty that out. I can't think of anything in particular that would make a whistling noise that would be in the range of "ok" operation.

 

[Snipeye]

The only thing (sorry for the necro) I can think of would be the inductor, because once the charge load drops to 0 because the battery is done, it's just eating up power. Inductors can whine audibly, I have a DIY USB charger that does it all the time.