What do you guys think of a device that can put to sleep those who hear it for 30 seconds? Too op even for high tier?

EDIT: I made you have to focus on the sound so if you can ignore it then it will have little to no effect. That will be fair.

EDIT: You know what? He's more fitting of an intermediate right now, especially with all his nonlethal stuff. I'll have him come in as intermediate and have an equipment drop come in later to upgrade his tier as desired. In that case I may have him go to Snek after all and loose his technology to explain why he doesn't have it any more. Maybe he gets killed by the henchmen or Jessibelle herself after realizing he couldn't use his weapons against her, and the tech is somehow destroyed or lost in the battle.