Not showing content

I have a xibo solution set up. The xibo CMS in install on Linux using docker, I have the xibo reader with and Android license, and the reader is connected to a ordinary computer monitor using the HDMI, I have uploaded my media to the Xibo CMS, created the layout , published, schedule . How do I get the media to be displayed on the computer monitor for testing then I would set up to the TV? Yes, I got it to working today, negative, I am using the DSCS95.