I have a Nokia 800 and 920. The USB charger that comes with it is giving out some high pitch noise. It's not loud, and probably many people won't notice it. But somehow I am tuned to such frequency.
It's the electric noise from the circuit. When I unplug the charger from power socket, it would still give out some noise for a couple seconds...
Has anybody experienced this? I wonder if Nokia can replace it with a good one or if they are all the same...
What you are hearing is the small transformer inside the charger vibrating. It's not something to worry about though as the charger isn't damaged. You can try and give the charger a couple of knocks which may or may not stop the noise. Not all chargers emit this high pitched sound so if it bothers you too much you could ask your nearest Nokia Care for a replacement.
There is no transformer in these powersupplies and there have not been for years. What you here is the capacitors used to switch power down 'singing' It won't be a problem right away, but I would recommend getting a new charger.
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