Well, seems that I have searched the forum properly for this question but nothing could be found... SO if there is an answer - please show me.
The question is: when I play Q3DM6ISH map I always hear two sounds of spawning bonuses: one is Quad Damage and the other one is a mistery

I know sometimes there are secret Invisibility or something (as on a Kaos map) etc.
Is it a glitch or is there another bonus realy?
Thank you.