Start soundbar with apple remote

I can start the TV with the ATV 4 remote as they are connected to each other with HDMI.

However, the soundbar is not connected to the ATV 4, but to the TV using optical. Therefore, the soundbar does not start with I press the ATV4 remote.

Is there some way to work around this problem?

I want the ATV4, TV and soundbar to start when i press one button on the ATV4 remote. Can anyone help me? 🙂

Thank you.