How to record audio in from external source - am i missing s

ive had the ren since day one but not needed to record audio in until today - ive just decided to sample some drums in from vinyl , im coming out of my mixer out and into the ren, ive selected line in switch and gone to the sample page. there is a signal showing but its not audio, its like a noise, I see what looks like audio signal on the akais 4 led lights on the unit and when I change the rec volume this changes but on the actual screen there seems like no input, I try recorded and it records nothing...

am I missing something here? surley it should just record straight in ?

any help would be great.

sorted now, looks like you have to have the ren selected as your sound card interface or it will be getting inputs from your soundcard which is my Yamaha o1v 96i desk.