[JAVA3D] Poor quality background images

[Robin Spark]

I'm having problems with the quality of background images.
My 2D background image is being displayed with a slight distortion. eg. horizontal lines are being displayed with jagged edges every centimetre or so.
I'm not using geometry, and the image is not scaled. I'm using the NO_SCALE_CENTER display property.

Does anyone know how to display a 2D image so it appears pixel perfect?

(I'm using the OpenGL implementation as I've read the quality of textures is much higher that Direct X.)

- Robin