How to stop mIRC beeping when I scroll up?

I know I might be posting this in the wrong place, but I’m getting really pissed off about it.
I join aos.aloha (staff will know that channel) and everytime I go up to look at something: BEEP. BE-BEEP. B-BEE-BE-BEEP.
It’s just so annoying. Dx

I know, you’re all gonna say ‘just don’t scroll up’, but when I’ve used Quakenet for 8 months straight, it’s hard to get used to that.
I can’t mute mIRC, because I still need to get notifications/highlights of stuff on the server.
I tried google, but nothing came to my rescue.
If you do read this and have no idea, please still comment so I know that you saw this.

Very much appreciated,
Chappy.

Tools → Options → Sounds → Uncheck buffer

Wow, I’m such a noob. Thanks color! ;D