Hi, I am not a IT tech guy by trade but it is my job right now to figure why we are having problems with HP laser Jet M4345 mfp, I have multiple 2nd tray problems. I will take it 1 problem at a time. 1st problem is I keep getting paper jam error message in 2nd tray when there is no paper jam. I have change the rollers and done basic cleaning. Took off back cover and tighten the spring on the paper pick -up assembly. Can that spring be to tight? Before when I had this problem I just made the spring tighter and the problem went away but I have adjusted this spring twice. I have also replace the paper pick-up assembly with a new one but I keep getting same error message. Any ideas what to do next?

Thank you
Ken