Stranche form corruption

We have a strange problem with one of our machines. We check out the
file from souce safe as usual, but we've noticed that when we do ANY
changes on the code, even adding something like

Dim strVariable as String

if we compare to the latest version on source safe there are changes to
the properties on the form, e.g. values like _ExtentX, _ExtentY are
modified in some controls, as well as the height and width!

What's even more strange is that most of the time the values seem to
have a constant offset.

Any ideas?

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