Sound effect of thief being played without need

[Felipefpl]

Playing trials of the luremaster again inside dragonspear made me remember of something that happens with the thief:

If you hide in shadows you hear a sound effect that shows obviously that you hid in shadows, the problem is: i hear the sound again from time to time and it's not because i left/hid in shadows again, i hear this sound when my thief is already in the shadows, this happens not only in luremaster but in the main game too.

[szaumoor]

That sound plays when your thief fails to hide in the shadows again each round, and gives you feedback it will lose the invisibility soon.

[Felipefpl]

That sound plays when your thief fails to hide in the shadows again each round, and gives you feedback it will lose the invisibility soon.

I see, except that this happens even when thief doesnt lose the invisibility. It happens right after i hide in shadows.