Default [Q] note 8 buttons flash after 4.2.2 update and strange files

Hi All
I just updated to 4.2.2 using STOCK Samsung OTA update in Portugal and have noticed that the menu and back buttons flash every so often, both at the same time, without me doing anything, anyone else have this, and any ideas what causes this???

and also I have seen that there is a file called emulated with 2 items in it a - file called O or 0 with a size of 5,65GB
and a file called legacy with 84 items in it with a size of 5,65 GB

thanks for any info