I am completely confused: I was just eating, when suddenly my computer started palying an old radio emission ( from about 5 months ago).

What most scares me is the fact that I do not use my computer for listening to radio. And I couldn't find out which program plays the sound. I use Clementine for music, but I could stop Clementine and the radio emission went on. It stopped when I did disconnect from Internet and did too when I closed Thunderbird. I really have absolutely no clue what to do!

Thank you in advance for the help!