[karlos]

Version 1.8.9 has no change compared to 1.8.8 that could lead to such a behaviour.
Check CVAR "mp_sank_sounds_obey_duration".

1 = Users have to obey
2 = Admin with internal flag "ACCESS_ADMIN" (default ADMIN_LEVEL_A) have to obey
4 = Admin with RCON flag have to obey

Add up each option that you want.
Eg: User + normal admins shall obey duration = 3

I do not know why this option is not part of the config.

EDIT:
I just noticed that there is an error when enabling obey duration for admins with "mp_sank_sounds_obey_duration". Will fix this.