After dying, dropped items become invisible, mobs as well

Experiencing issues with items disappearing after dying and respawning. If I am in a singleplayer world, I can still pick them up by running into them but if I am in a multiplayer world I can't even do that but the other person can. 

 

Mobs are also invisible and don't seem to be effected by daytime if they are hostile. 

 

I have debugging turned on but no errors or warnings appear.