Is there another way to disable fields aside from GET_I* and business roles?

Hello All.

We're facing a problem wherein, when we add new items with a certain item type, the line item becomes disabled. The quantity and item status and some other fields can not be edited.

Upon checking the GET_I* method, rv_disabled is false, but the field is still disabled.

If we select another item type before pressing enter, the line item is editable.

We are not aware of any ABAP development that could cause this, though we are not 100% sure.

Is there another method where we could start debugging from that will cause the fields to be disabled?

Thanks for you help.

-Phil