Random Spawnpoint Via minecraft_server.jar

Well, When in my server run simply by the minecraft_server.jar

Whenever me or other players also, respawn, It takes them to random locations, instead of one spawn point. I've tried going into creative and using the /kill command, And trying to see if it would ever take me to the default spawn but it never works. This never happened to me until the recent updates, so that may have something to do with it.

Oh, Also, It actually only been happening since i tried adding spawn-protection= to my server.properties. I tried removing it and restarting the server, but the problem still occured, Just thought i should mention it, incase its linked somehow.