seconds… after the initial reading of the card on boot, which can take up to a min depending on the size of the card…
in terms of loading from the card, that is a no.
You have to preload from the card any songs you want to the pads… to access the sd card, is its own separate function, and you cannot access or play anything while accessing the menu…
once on the pads, you can then cue and play from dj mode.
even with loading from the app, it stops the functions to load the pads.
EDIT: I should clarify… it reads the sd card once you access the card menu AFTER every boot, not on boot.