reloop usb mixer

hi all…first post for me…looking for someone to explain in simple terms how i go about setting things up.
I have just bought a reloop usb mixer which has 2 usb ports - this allows me to use mp3 files in the mix but also to record the whole thing…apparently!!
I have hooked up the 2 usb’s and can play mp3’s through my mixer but am still unable to record anything

I have tried to follow the setup in preferences and thought all was correct but apparently not…any thoughts , comments or help would be greatly appreciated - thanks!

Reloop makes a pile of mixers. Which One?


You almost told us which Computer and Operating System.