Okay, I remember your posts.
It seems to me it is time to do some housekeeping since your files keep getting hosed.
You can start with the control panel and delete any and all access to the control panel including changing the password for yourself.
If there is somebody you really trust then change that persons password.
Next change your MySQL user and password setting.
Next delete and or change all ftp accounts.
Finally change your master account login with your host.
You need to do this all at once because not knowing what access somebody has they may get to something while making the changes.
Once that is done then try some fresh files and see if something happens.
Then follow Ricks advice to look for datestamps on changes.
