Hi,
Normally when fighting Slothasor you get a small “beep” when he begins to Fixates you. But since the introduction of Wing 3 there is no more Sound on a Fixation at Slothasor. The Sound was really helpful because you have so many Visual Noise there which makes it hard to see if you are fixated.
At KC we ( my Raiding Group ) thought that it was intended for the Fixation to have no Sound but since the Bombs ( which everyone gets ) have a Sound and the Fixation Sound at Sloth vanished I’m sure that this is unintended and a Bug.