Post any defects you find in the released or beta versions of the ImageMagick software here. Include the ImageMagick version, OS, and any command-line required to reproduce the problem. Got a patch for a bug? Post it here.
Yeah - I get this consistently, and have done for the last few versions of IM.
It only seems to happen for small images. If you up the size to 15x18 or larger, it should work fine. Not a great solution, but the only one I've found to date.