Help Line in 3 and 4 not working?

I connect cd and pickup and do not sound …1 & 2 working good !

Hello I do apologise about this issue you are having. Our technical support team will be able to assist: https://denondj.com/support

Line / Phono switches on the back of the controller?

Have you changed the input switches over to LINE ? for Channel 3 and 4.