THAT is never a good sound when sewing. My Pfaff (the one I just had serviced a month ago) did the klunk yesterday and it seized up. I reset the machine and got a few more seams out of it. I petted and talked nicely to it, but when I cleaned the bobbin case, a small piece of metal fell out.
:cry: Looks like a visit to the ER is necessary - hope they can do CPR.