Akregator fetches old news and stores them elsewhere

Hello everyone,

for a few days (about a week) i've had the problem that akregator is fetching 
some old feeds and storing them in other news folders. The folders selected by 
Akregator for saving vary. Today (until 9 a.m. CEST) I had to delete about 400 
feeds.
By the way. The 'Delete' button doesn't always work. Sometimes I need the 
mouse for that.
New feeds are saved correctly, so only old feeds already marked as read are 
affected.

Any help is welcome!

Regards,

Andreas