As of 1530 today (Sunday). the TfL syndicated XML feed is running 45 minutes behind real-time, as reported by the timestamp in the XML.
While this may not be possible to fix if you are having wider system problems, as far as I can tell this data is being used on the live TfL map. A quick spot check certainly suggested this is the case, and your syndicated feeds website says it is so.
However, the infoWindow popups on the TfL map were reporting the current time (15:26) as the time the data was valid from – which is quite misleading, since the source data was reporting itself as almost an hour old. This at least should be a simple bug to fix.