Dynamic container and news

Hi there,
I’ve got a strange problem since this week.
We have a dynamic container for news which is composed by :

  • intro jingle
  • local news that we produce and which is overwriting the file from day before
  • bumper
  • national news that we download from a ftp server and which is overwriting news from the day before
  • news outro

Last week , it worked.
Each news element has the don’t do prebuffer option activated.
Since this Monday, the national news from the day before is heard. So the audio file is not existing anymore and has been replaced by news from today.
When we are listening the element news itself in database , it’s the correct file.
So it seems that the file is staying in the cache of the computer ?
I don’t manage to correct that for the moment.