Incremental Backup Programme for Digita Programme Data

The backup programme supplied by Digita does not do incremental backups, and as a result, my Digita data backups get bigger every day, even when I have not touched the original files. I understand this is a result of Digita products using MSSQL.

Does anyone know of a backup programme that would automatically back up my Digita data files on an incremental basis, instead of copying identical files every time?
Tom Trainer