Not sure if this occurs elsewhere, but I was in Cyrodiil when this started happening to me and a few guild mates. It seems that this started happening about a couple of hours ago. I had to leave since it got so bad.
1. Voice chat kept joining and leaving group chat
2. Constant lag - it appeared as though our characters could ran very fast only to be teleported back a few seconds later.
3. Robotic voices (when group chat did manage to cooperate)
4. Unable to mount/stealth
5. Seige took forever to shoot.
I do have a fast internet connection and was able to play other multiplayer games - which leads me to believe that this is a server issue and not a PS4 or user issue.
I sent in a ticket, but am also making this post for good measure.
Saw a mudcrab the other day. Dreadful creatures.