Problem with smart previews / originals

I am using the current version of lightroom with preferences set to store a copy of originals on my hard drive. In some cases, the preview shown in the grid differs from the image shown in detail. For example the preview is the right way up, the detail is rotated upside down. If I rotate either the preview or the detail, the images are rotated but still differ. Does anyone have an idea?

Thanks, David

On looking more carefully, it seems that the problem is related to the local storage of originals. If I delete the local copy, things are ok again but I seem to loose the last edits. It appears that edits made on my notebook are not reflected in the copy of the original on my mac - the preview is current but in detail the "old" original is shown.