Sound Bugs are mainframe devices found in Sankaku missions of difficulty 2 and higher. They can also be found in some Vault objective rooms. They allow the corporation to hear any sound that an agent or human guard would on that tile, triggering an alarm response when any unrecognized sound occurs.
If a noise caused by the agency is heard by a Sound Bug, they will alert all guards from a Euclidean distance of 12 or less from the Sound Bug and raise the alarm level by 1. All alerted guards will become interested in the source of the noise. This happens at most once per turn per Sound Bugs, so even if another noise is detected by the sound bug in the same turn, the interest point will always be the first tile where that Sound Bugs heard a noise that turn, and the alarm tracker is not raised further. A pulsing red line leading up to a circle will eminate upwards from triggered sound bugs.
|Sound||Triggers unhacked Sound Bug?|
|Cry Baby activating||Yes|
|EMP Pack detonation||No*|
|All sounds by human guards||No|
|Unhacked drones firing||No|
|Hacked drones firing||Yes|
|Unhacked turrets firing||Yes|
|Hacked turrets firing||Yes|
|Recaptured turrets firing||No|
Sound Bugs are much more punishing than Security Cameras - one sound can alert the entire facility under the wrong circumstances. Sprinting should be avoided in Sankaku missions of difficulty 2 and higher unless you are sure there are no unhacked sound bugs that can hear you. This can make sprint toggling to distract human guards more difficult, so plan accordingly.
The presence of Sound Bugs also makes killing Security Cameras or guards using hacked drones a dangerous and often costly move on these missions, since drones make noise in a range of 8 tiles when doing so.
With that being said, hacking Sound Bugs is rarely advisable unless the agency has a lot of PWR to spare or there's an immediate need to do so, since Sankaku will often have a lot of other things you need to hack, and making noise isn't usually necessary.