Hello, I bought a slightly used machine from a dealer who is a Long arm quilter. She is quite helpful. However, we are stumped. I have been quilting along swimmingly with all manner of conditions and thread but now I have what I call a grinding noise. When my sister is running the machine and I stand on the back I and put my ear to the head of the machine it seems to come from the area above and inside, behind and away from the tension disks. Of course we have done all....thread, needle, bobbin, clean, oil, etc. the stitch, believe it or not looks "okay", not great , but okay. This happened once before and it stopped after the usual cleanings and oilings and a little quilting. My husband the mechanic says one shouldn't drive on with a suspicious noise like I have. Any thoughts? I have read through the forum and haven't seen this problem mentioned. The machine was quilting along fine when this noise started.