I used to have my system set for 'visual system beep' doing this made my screen flash, and as far as I could tell I didn't have any error beep when, for example, I tried to backspace one too many times in a browser window. I was happy with this.

But now, the screen does no flash and I get a really annoying beep when I do this. It's driving me crazy. The 'enable system beep' checkbox is still unchecked, and the visual system beep box is still checked. I've blacklisted my pcspkr and everything. It won't go away. I want my computer to be silent!