When player destroys rebels' Power Coupling, it happen sometimes that blue uniform guards in the secret room are not properly alarmed, and only one or two of them become active. Sometimes they even cannot teleport, because other guards close their way to teleporting lines. As a result game stuck on this quest forever.
I am not sure why this happen, either PowerCoupling does not send alerting message properly, or sound traverses improperly, cannot say. I tried DOS Strife few times, and couldn't reproduce this bug.