Well I fixed it. Since it was only happening in one scene I deleted objects one by one and resaved. Then reopened the file to see if it was fixed. If not I moved on to another object. The offending object was a surface replicator. With it gone from the scene the interactive renderings settings changed and updated as they should. What the problem is I do not know. I have a copy of the original scene that was causing the problem, perhaps Eovia can shed some light on it.