Simp=ly, I do have the ability to go back and delete the p=. What hap=ens is when I dep=ress the equal sign, I also get the p=,and the cursor jump=s back to the first row of typ=e.
There is very good advise in diagnosing and fixing your problem here already. There are also viruses that affect your keyboard buffer. What anti-virus do you use and is kept up to date? I highly recommend Nod32 which updates its signatures daily.