1) try new clips as said above . Yours may be foreign or just old and " sprung out " .
2) Could be dangerous. Take it out and check for the bolt to fully lock up before each shot. You may be using hammer energy to push the bolt closed and not have enough left for firing. This is dangerous because of the chance of an out of battery discharge. Could be one of many causes...ammo out of spec , somthing rubbing on something ( op rod to stock , for example ) , tired mainspring , not enough lube and/or not where needed, etc.
3) Hammer is caught by the sear on one set of hooks when the bolt cocks it , then transfers to the trigger / other set of hooks when the trigger is released. Then it is freed when the trigger is repulled . This first catch should happen far before the bolt rides back enough to eject and reload , so if it's doing that , you're not short stroking . Check the hooks for wear , check for movement , check for crud and blockage. When you recock by hand , you've released the trigger so the hammer is caught by the trigger and those hammer hooks and never even touches the sear nor uses the sear hammer hooks. The problem is prob'ly in the sear or those mating hooks.
HTH , Chris