Depending on the AJA device you can connect the LTC source to the shared Ref/TC connector or directly to the native LTCin connector. In addition, we also support LTC In using the mic input of the Mac.
In the just:out preferences you can then select the LTCin as your master timecode source. In case the resync function is activated, just:out will resync to the master time at the end of each playlist for a maximum of 5 frames. This resync can be turned off for each playlist individually in just:plays inspector.