Content Type of Source lost

Hi there,

I now several times had the problem that FRODO lost the content type of movie sources. It is a big problem If you don't realize it and then clean the database. It will wipe all the metadata for that source. When you set the content type back again you have mark stuff as (un)watched and correct the metadata, which is highly annoying for a large library.

The source is located on an AFP volume on a Synology DSM 4.1 NAS.

Does anyone know under what circumstances XBMC (here FRODO RC3) loses the content type of a source and how it can be prevented?

Thanks in advance,
JC