Nexus Turret continuous firing sound bug

I've had a sound bug occur a few times since the new rift came out. It appears to happen once super minions are within range of the nexus turrets. For some reason even after having killed the minions and the turrets have no more targets the fizzling laser sound will continue as though the turret were still attacking. the sound goes away if you leave the area of the turrets and is audible only while the screen is near them. It also seems to fix itself sometimes if the turrets get new targets. Just kind of an annoying bug.