If you enter any server with at least 2 people in total with vehicle smokes enabled (Ifrit/Strider), firing the smoke countermeasure will cause the smoke canisters to play multiple more collision sounds than expected.
The extra sounds do NOT play when you are playing locally or on a server with only one player.
I assume this is causing more network traffic than normal, however I have nothing to backup that claim.
This can be replicated on every Arma 3 server I have been able to test, including a base VR world I loaded onto my own server with loopback.
I did not test if it is creating multiple invisible smoke objects, but none are visible when this occurs.
I attempted to run the countermeasure code on my player, instead of executing from a vehicle, and it did not cause the sound bug.
It is present in servers and clients all running the latest 2.18 v8 profiling build as well as server/clients running 2.18 Stable
Bit of an update to this; Running Stable? Build 152405 (Will test with v12 prof later), with 30 people on the server and monitoring Outbound with #monitor 0.1 with client.
Tested 10 times
Normal and consistent values 700 to 1.9Kb/s, small spikes of 2.8Kb/s.
Spawning vehicles from server, no drop.
Hit ifrit countermeaure, outbound jumps to 20k-40k Kb/s when smokes land (physx calculation?).
Used these 4 times in quick succession, noticeable delay in return from #monitor, and outbound jumped to around 70k-100k Kb/s
Throw normal smoke grenades, no noticeable issue.
Shortly after, network returned to normal each time.
During testing, 10 more people joined, and the network per countermeasure seemed to increase by a noticeable margin.
Thread of this in Discord Feedback tracker: https://discord.com/channels/105462288051380224/1310192027534753802