There's hardly any known problems that occur with the electric power steering. Usually if you're having weird problems with it, you need to check the condition of your battery and battery connections as the power steering heavily rely's on good power from your battery and stable connections to it.

 

Mine does that too; has ever since I first got it over a year ago. Doesn't seem to be a huge issue that needs to be addressed immediately. Definitely make sure the battery is in good health but it's not a large cause for concern unless you start noticing the steering getting heavier.

 

I would guess (and it's only a guess) that the increased electrical load could possibly cause the alternator to whine.