Why is texture blurred in one GuiStyle and not in another?

I’ve had a problem when designing the GUI for a mobile game - the textures (from Kenny’s UI pack Assets · Kenney) are drawn with some pixelation around the edges. I’ve imported them as sprites with all the recommended settings. The oddest thing is that in my GUISkin the button texture is drawn perfectly crisp and clean, yet the label style background (even when set to the same sprite as the button style is using, drawn at the same size!) is being drawn with this pixelation problem.

28441-button.png
<—Button being drawn perfectly

28442-label.png<—Label, drawn at the same size with the same texture. Note the pixelation in the corners.

It may be worth noting that I initially had the blurring problem with all my textures, I have no idea what fixed it in the Button style of the GuiSkin (I have a suspicion that I added it to the style as a texture, then changed the importer to sprite, though that doesn’t solve the label problem so possibly that did nothing).

Can anybody help me to fix/explain this behaviour?

This is usually caused by different Border properties. Make sure they’re the same in both styles

http://docs.unity3d.com/Manual/class-GUIStyle.html