On some feeds, e.g.
i do not see the latest item in the feed in feed on feeds.
Only when a new item the previously latest item becomes
visible in feed on feeds. I had a quick look at the source
and my database, i get the impression the <link> and <guid>
in the feed are not permanent/unique for the item. Which
I guess would be hard to fix.
Hopefully I will have some time later to look into it