External Mixer + Performance Mode = Low Output Volume

Hi,

When I run Rekordbox (4.0.8) in performance mode and external mixer - my output is very low. All routing is perfect and channels are assigned accordingly.

In comparison to LINE/PHONO, I have to have the trim turned up by nearly double. When i flick between internal/external mixer inside Rekordbox, the output volume goes back to normal, and then back to quiet again when selected on external mode.

Is there a function I'm missing when using external mixing mode to achieve a normal output volume on my channels ?