With having the "Make defaults specific to camero ISO settings" option enabled in the Preferences, the action of setting a new default development setting (Alt + Set default...) sometimes overwrites an existing setting, but valid for another ISO value.
I've identified that the problem is occuring when for instance updating a default setting for ISO 160... which ends in updating the existing setting for ISO 1600.
Same for ISO 320 and ISO 3200. Always this x10 factor.
This can be seen in the CameraRaw Defaults folder where xmp files gets overwritten.
I can see that the KeyString attribute in this file is made of the concatenation of the camera model and ISO value:
crs:KeyString="Canon EOS 7D ISO 160"
I assume there's a bug in the way Lightroom or CamerRaw is looking for the correct settings file and picks up the wrong one.
I've noticed that with Lightroom 6.8, on Windows 7 x64. This is very annoying!
Adobe, can you please fix this?
Please repost this as a bug report in the official Adobe feedback forum, where Adobe wants all bug reports submitted: Photoshop Lightroom | Photoshop Family Customer Community . This forum is primarily a user-to-user forum, and Adobe product developers are rarely seen here.
To make it more likely your bug report will have an impact, follow these guidelines. Make the subject line a concise statement, e.g. Lightroom: ISO-specific defaults for 1600 overwrite defaults for 160. Then provide a short 2- or 3-sentence summary of the bug. Then provide numbered, precise steps for reproducing the bug that any Adobe employee could follow without specific technical knowledge.