I looked and I looked, but I can't seem to find a way to turn off the sounds when things like "That ability isn't ready yet" or "No Target" error messages pop up. This is annoying as it gets louder with more of these errors popping up at once. Due to the lack of in-game macro's I use and map multiple keybinds to my G13.
When I have both of my relics on cooldown and another ability on cooldown bound to my hammer shot, it's very noticeable. Especially since as a tanking vanguard I use hammer shot a lot. So please If anyone knows of a way to turn this (and just this, not SFX all together) off please let me know. Otherwise, I don't know if I'll be able to deal with this for very long.