Unknown Device Showed Up In Network Security Map

Hi!!

First at all sorry for my ​E​nglish!!

I´m testing Norton360 ​with all its options. ​Meanwhile testing Norton security map I've observed ​the following situation:

  This program present all the devices conected ​to ​ the router  correctly but ​it is also appearing another one marked ​as:

               NEW

              Category: DesktopPC

              Remote Monitoring OFF

              Conection Offline

              Excluded from IPS NO

and a Physical address (MAC) whitout IP adress resolved. ( The IP  label ​does not appear )

​At that moment, ​I ​checked in the router all the conections, and ​ realized that ​this ​unknown MAC ​was not appear​ing​ in the IPs connected to the router ( all of them corrects )

After that, ​I ​discon​n​ect​ed​ the router fisica​lly from PC and... all the connections disasapear​ed​ from  Norton Security Map, except the  MAC​ one​.

​Then I disconect​ed​ fisica​lly the router from the PC and restart​ed the​ PC.

​I checked again the Network security map and... the "weird" MAC ​was there.

​I finnally supposse that this is the MAC ​of a dispositive linked to the PC​ but I have been unable to locate it:​ maybe is the printer, the wireless keyboard or the network card or any other dispositive

.​ I would like to be sure about it.​

Any Ideas??

Thanks in advance!!