may be wandering because they have no set place to be.
With arrange by none and sort by none I'm not surprised that they move.
Since going to Lion, many icons in icon view won't stay put. I set arrange by none, sort by none and always open in icon view. This is also the default. This happens on the system drive and on mounted external drives. The issue is not consistent. Sometimes a folder will rearrange icon positions and sometimes it doesn't. Any ideas or just wait for a fix from Apple? As I recollect, there were flaky things about icon locations in 10.6 but they went away after a bit.

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