Check your desynch value (press P and click your name). It's probably 100000 (the maximum). Had a similar issue in an older version of DayZ SA where my client only got information when joining (items on the ground, players somewhere close). I could run around and my friends would see that but on my client they were standing on the position they were when i joined. They weren't not moving or doing anything.

I couldn't do anything about it. Sometimes it worked on some servers but got desynch like 30min later. I think Dean said that this was caused by problems with weather synchronisation. Maybe theses desynchs are somehow related.