This is often caused by a corrupt Title Update. Delete your cache and re-download the TU through Aurora.
Aurora will typically "merge" these into a single icon. When you reach the end of a disc's content, the RGH plugin (Dashlaunch) will usually handle the swap automatically. Essential Plugins and Dashlaunch Settings la noire xbox 360 rgh
Use a tool like or 360MPT to convert your disc images. This is often caused by a corrupt Title Update