This is most probably caused by the communication problems between your site and the RSS source. Is the caching enabled on your part (click on Properties in the admin mode and check the "Cache duration in seconds").
Could you let us know which URL are you using as a source of data for this module, so we could test it ourselves?

I actually have the same problem..

I noticed it.. but been putting it off..
Bu sometimes... the feed dont show up..

http://www.thepittsburghscene.com/

The feed is right there and its a yahoo pipes feed.
Music News Around Pittsburgh

It does sometimes just not show up..
we played with catching.. we have it currently set to 30 seconds

I have the cache set at 500 seconds and the timeout at 60 seconds.

RSS feed is :http://iol.co.za/cmlink/1.640

Hi,

  can you please check if the System EventViewer for an ASP.NET has any error related to MonoX RSS ?

Thanks

Francois, your settings are correct - it does not make too much sense to use the RSS reader without caching, as it would contact the RSS source on each page hit and slow down the page execution cycle. We will do some tests on both URLs you guys provided, to see if they are constantly available. The behavior you described signifies that our RSS part cannot access and/or parse the RSS data after the cache period is over, and we'll try to get the same behavior on our end.

Hi Francois,
We have tested your URL and it appears that it times out from time to time (approx 3-4 timeouts on 100 page hits, each of them 2-5 seconds apart). We will add more diagnostic options and clear the cache on error in the next minor release so you will be able to see the exact error message.

Thanks for the feedback.