Two maps in a row my Cata runs were ended by silent chaos patrols aggro’ing with no sound to announce their presence.
The locations were Athel in the canyon past the riverbed, and Hunger in the Dark in the long straight tunnel by the first grim. I don’t know if the patrols were stationary, marching silent, or simply spawned in. In both instances, the first my team was aware of the patrol was the huge horde of CW on top of us.
I play VT with volume maxed and no background music due to the importance of sound cues. In both instances, the group was not fighting a horde so it was relatively quiet and I am 100% sure I heard no patrols.
Encountered several SV patrols and they all marched normally with the correct sounds. Hope this can be fixed soon as it ruins Cata.