When joining a coop match and even though my suppressor is on it's sometimes not but only in coop. It seems that the host's game determines whether or not the person who joins is suppressed. A work around is to ask the host to visually check but it's a real pain and prevents you from splitting up as you'll never know if you're suppressed or not.
My suppressor was on and I was at 200m and it alerts all of the enemies. It's so bad the my coop partner and I made a rule that the person who joins must ask, "am I suppressed" and visually verfify it before firing the sniper rifle. In this case the HTI. This has happened numerous times. I'm not sure if it's a desync issue or an actual bug. I have never had it happen on any other weapon type, just snipers. At least in my experience.
Thank you all for reporting this bug to us! This is an issue that has been shared along to the team for further investigation.
See http://forums.ubi.com/showthread.php...in-Coop-Forums for more info.