There are a few things that trigger communication outside of the collection interval (see here for more information).
As you have a static layout it is unlikely to be a “resource download”, which leaves:
- downloading library media - i.e. stored files.
- notifying the current layout (if switched on)
- sending a screenshot (if switched on)
Stats/Logs, etc are only sent every collection interval.
Do you have any error messages on the status screen of the player itself? Perhaps it is having trouble saving a file and therefore attempted a repeat download.