Symbols not monospaced on Mac

[trap15]

Even on monospace fonts, all characters except for space, and alpha-numerics are not the same width as the rest of the characters. Some are 1, 2, or even 3 pixels too thin. I have tried all the monospace fonts (Courier, Courier New, Monaco, etc.), and they all have this issue, though some have it worse (!) than others.

It's not super-crippling, but it makes my OCD go haywire.