My best guess is that its in their best intrist not to. We know the navy has super precise microphones underwater to detect weapons feasting both conventional

My best guess is that its in their best intrist not to. We know the navy has super precise microphones underwater to detect weapons feasting both conventional and nuclear, as well as using the sensors to monitor for ship activity....like sub's or unmanned water drones. I'd assume that if they release any info on if they heard something via a sub or some sensor.....its basically burning an intelligence asset, as it can reveal information about the actual sensor and possibly it's general area. Best option would be to just stay silent and deny if asked, and refuse any FOIA request on the grounds that releasing sensor data even if its not the raw data could lessen the effectiveness of our Intel/sensor network.