Strange Behaviour with keyframes on Enum Attributes

Have been experimenting with enums to create different space switch setups and noticed some weird behaviour when adding keyframes. When I add keyframes to the enum attribute, the keyframes seem to be overwritten by whatever value I last set the attribute. The only way to make it act normal is to enter the graph editor and that causes it to act normal. Not sure what is causing it to act this way. Any thoughts?