I have a 2017 Thor class c motor home, bought from individual that originally bought at camping world meridian. And I am having a problem with the Sony CD DVD player. I want to play music cds but can't figure it out. Can you give me any idea

Why not just download the user manual from the internet and read the instructions...

Have you tried changing the source? It needs to be manually put on the correct setting. It may be on the DVD setting. So it's trying to play them through your TV and not the speakers.

I would take it to a radio shop like car toys or whomever and ask them. Camping world might know as well. Start there then try a radio place