Headphone noise comes out while broadcasting

[Fhughes2]

Hello all, I am new to obs and I would like to use it for broadcasting. I use virtual dj and pioneer ddj400s. When I use these without obs it works normal, as soon as I broadcast the music I have in my headphones that I am ready to play next can be heard through the stream. I'm using an asos notebook on Windows 11. Your help would be appreciated. Many thanks