DDJ 400 not working as a controller

My DDJ 400 works perfectly on my laptop but since switching to my desktop it doesnt work. It lights up and says ddj 400 connected on Rekordbox but nothing works. I even tried it on Virtual DJ and its fine so the problem seems to be Rekordbox. I've done a firmware update and tried reinstalling Rekordbox but nothings worked so far. Can anyone help please.