To hear hum / noise - not good

When switching hear a hum / noise / high tone. This probably comes from the speakers. On the Internet there are no information on the manufacturer to find. Also on the packaging or the English not manual. Amazon has nevertheless caused a replacement. Still angry because I have to take extra time off me for pick up and delivery of freight forwarding.

Today the Erstazgerät has come. It brummmt just as unpleasant. The unit can now be a second and pick up times letzes Amazon. With a droning piano can nobody do something! And I can take me for picking a 3rd day free!