Paper not feeding correctly into epson cx4800

(1) All of a sudden the paper feeding into my epson cx4800 isn't feeding properly when I go to print something. sometimes it won't "grab" the paper at all and other times it will grab it but print too high or too low on the paper. checked to see if there was something stuck in mechanism, can't see anything. (2) Also, when I want to make a copy of a document, I lay it on the glass, set the copy counter to "1", press "start B&W", and the paper jams and the error light comes on - it won't let me clear it so I have to turn the machine off. Any ideas?