Master button/indicator not switching

Hi,

Just bought XDJ-XZ (great product!).

However, noticing when I mix from either Channel/Deck, the MASTER indicator is not changing for some reason. Even with the fader completely down on the outgoing track, the orange MASTER light still shows up on that deck. Only when I stop the track playing does it switch to the other live deck.

Any help on how to troubleshoot/fix this is appreciated.

Thanks