I have to come back on this again. Every time I download data when I open up WC, it states the number of files/records to download, but also in brackets there is still this constant - 512 files to download. This seems to be similar to what Jamesmb is saying.
Also one other point, I run Windows on my Mac through Parallels, as I have two softwares for my bird ringing and moth recording that are not compatible with a Mac. Now if I go into these to work and WC is running, when I get put of Windows, WC seems to download continuously. It does not seem to affect any data, but in order for WC to run correctly again I have to stop it and restart. So, if anyone does run Windows via Parallels on their Mac be aware of this.
Bryan