This screenshot shows a script I have used to tell Alexa to switch on my Ruark internet radio. Ruark, like many other smart radio manufacturers, uses a chipset from Frontier Silicon, to control DAB, FM and internet radio as well as stream Bluetooth audio and music from DLNA music servers.
I found some excellent documentation here on GitHub for controlling these radios.
In my setup, the dimming command is used to change the volume. I say: “Alexa, set Ruark to 10,”to increase the volume by 10.
I also get it to go to sleep after 300 seconds (ie five minutes), rather than switch off instantly when I say: “Alexa, switch off Ruark.”