XDJ-RX - issue with tracks appearing unanalysed

Been using my XDJ for six months now and love it.

However, in the last few days a really annoying issue has started.

Tonight for example, I was mixing and then all of a sudden the next track I loaded in I got a message saying "Rekordbox analysis needed for Quantize Feature"

This track had definitely been analysed and had worked a hundred times before.

I tried with more tracks, same for every single one I loaded.

I rebooted the XDJ, and the first track appeared fine, but subsequent tracks, the same issue.

I have already updated the software to Version 2.21

The next thing I am going to try is formatting the USB and starting again.

Anyone else had a similar issue or may have an idea what is going on ?