This pattern worked for me;
http://www.dnasir.com/2013/06/26/saving-loading-episerver-plugin-configuration-settings-using-dds/
I don't know exactly what was causing it.. but using a singleton pattern did the trick.
I had the same problem as well! EPi 7.5.394.2 & Commerce 7.5.
Solution: rewrite dds functionality to use repository & singleton pattern according to this: http://www.dnasir.com/2013/06/26/saving-loading-episerver-plugin-configuration-settings-using-dds/
I am getting the following error in my log file:
ERROR EPiServer.Packaging.Storage.StateStorage: There are more than one record in StorageUpdateEntity data store for server with id {guid}. Extra records will be deleted.
Not sure if it's connected, but I get the following javascript error first time I load the CMS after a build:
GET http://mysite.local/adminpath/cms/Stores/contentversion/?sort(-savedDate)&dojo.preventCache=1395328653994 400 (The contentLink parameter is required.) dojo.js:15
_30e {stack: "Error: Unable to load /adminpath/cms/Stores/content…l/7.6.2.0/ClientResources/dojo/dojo.js:15:132269)", message: "Unable to load /adminpath/cms/Stores/contentversion…Date)&dojo.preventCache=1395328653994 status: 400", response: Object, status: 400, responseText: ""…}
If I clear the errror and refresh, it doesn't come back. and loading http://mysite.local/adminpath/cms/Stores/contentversion/?sort(-savedDate)&dojo.preventCache=1395328653994 in the browser doesn't return any errors.