Question about Samsung Hw-N400

How did you solve that? I have also lost the power cable :(

Samsung Electronics GmbH
Hello,
please contact us via one of our support channels. Click on "Support" on the Samsung website and select "Hotline" in the submenu. There you will get an overview of all contact options.
Best regards from Schwalbach,
Your Samsung Service Team

Of course, you can buy all the supplied cables separately, but which one do you mean? The power cable?