BC118 switched to MelodySmart OT


One of my customers is using the BC118 in one of their products. Many of their products are already deployed in the field. Recently one of the products returned from the field, unable to connect with a smart phone. After some investigation, it was determined that the module identified itself as MelodySmart OT. The customer resolved this by using the proper recovery steps.

The question is: How is it possible that the BC118 enters the OTAU modes without purpose? Is the above described situation a known issue? Can it be avoided?

All input is welcome.