Originally Posted by lauraspeer
Yes, the top stitch looks great but the bottom looks like that. I thought maybe the tension, so I played with adjusting that, I switched threads both top and bobbin thread too. I just don't know what else to try.
It looks like there may be some lint or thread either caught in the bobbin or tension discs. Take the plate off the machine and give the bobbin race a thorough clean and oil and check the tension discs and change the actual bobbin that you are using. If it still doesn't rectify, it will be time for the technician.