What is the current value now ?
Also is the feed online?

Value of Feed timeout (in seconds) is now 29

I do not understand your question about feed online
If its the rss feed to fetch you mean :
its www.amnesty.fr/RSS/Actualites
and yes its online


EDIT :
I purged cache and the error disappeared
Perhaps you have any explication ?

OK, the feed is online.
The error is gone because the extension pulled the feed again and it has items to parse.

That error indicated that no items where available when the extension was trying to print the items in the front-end.

Krikor wrote: That error indicated that no items where available when the extension was trying to print the items in the front-end.

Yes I understand but why du I need to delete cache so that the extension works again ?

It is possible that the feed that was stored was either not valid or not properly downloaded.
Clearing the cache forced the extension to get a fresh copy of the feed.