Thief Gun Sounds Not Present in Event

[Xineizer.5490]

I have a lvl80 Thief that I used at Verdant Brink. Whenever an event starts, the gun sound effects of my pistols are not present. I can hear the sound at times, but 80% of the time, it's not there. When the event ends, I try using the skill again, the sounds are present. This applies to Skill 1 and Skill 3, when dual-wielding pistols.

If I use my Ranger/Soulbeast, there are no problems with sound even with the rapid fire of the longbow (Skill 2).

Is this a bug in the game? I've searched the internet and can't seem to find any information on gun sound problems with a Thief.

Losing the gun sound in the game totally removes any game immersion. I might as well play the game in silent mode.