No. You shouldn’t need a preamp since it is a line out.
Make sure you have the input switched to mic/line and not Guitar. Also, maybe obvious (but a woman at my work accidentally flipped the mouse for her computer upside down and amazingly didn’t notice anything wrong, like all movements where inverted etc, until she couldn’t click with the mouse....we shared a good laugh about that when I showed her that the mouse she used the mouse the wrong way.), so I will ask anyway, make sure you have turned on the best bras preamp thing. It needs to be on even if you are not using the headphones for the mic to work.
Otherwise I have no idea:/