u/Educational-Newt7080

I thought the peak meter in Logic pro was supposed to be calibrated to -18dbfs while the TBProAudio vumeter is at 0. When I am tracking the vu meter is bouncing around 0, but the logic peak averages around -10 ish? What am I missing? I have made sure the TBvu meter is set correctly. Please, any help will be very appreciated. Thank you