DDJ 400 Audio Delay b/w master output and cue headphone

I brought ddj 400 online and it was all good but i didn't used much and had replace by new one due to ddj 400 not being leveled on tabled. When i got replaced one , i notice delay between cue headphones and monitor speakers which i didn't noticed on older piece . I tried to remove all additional hardware and listen directly from laptop still lag. Its very minor but it irritates me . Is there any solution to work on ? FYI i tried decreasing buffer size from 5.8 to 1.1 still an issue . I didn't noticed problem on older version (i don't know i checked playing same song on both things , but i might have tried that and experienced no problem that's why i don't remember) Is it hardware problem ? Help me out