Bug Report: Probably not worth a support ticket:
Whilst playing this afternoon, the deck abruptly stopped both playing decks. The 2 AIFF files were playing at the same time from a Sandisk Extreme Pro USB formatted to HFS+.
Play buttons non responsive, all other buttons are working fine, so it's not a freeze. Trying to load another track brings up the message "PAUSE track or set LOAD LOCK TO UNLOCK IN UTILITY", so under the hood and according to the play / cue buttons, the unit is still in "play" state. Changing the LOAD lock made no difference, It would load a new track, but would not play it when play is pressed.
Zooming still works, jog wheels do nothing. Tried to add NOISE Color FX to see if there was still an audio path in this state, no sound, just silence, all meters still off. All working perfectly since boot up 2 hours prior.
A Reboot and order is now restored.