Dice has released a lot of patches for Battlefield 4 but it's still far from perfect. The latest patch released on 20 Dec brings back lag, lag spikes, frame drops and a bug that is causing crashes on the xbox 360. Dice is currently monitoring these issues to find a solution.
via N4G: pc news feed http://n4g.com/news/1427686/battlefield-4-connectivity-and-netcode-issues-on-all-platforms
via N4G: pc news feed http://n4g.com/news/1427686/battlefield-4-connectivity-and-netcode-issues-on-all-platforms