Use different thread.
Clean the bobbin race
Clean under the bobbin race.
Change the bobbin race
Different stabilisers (tearaway, cutaway, vinyl, filmoplast)
Go in to the "here be dragons" part of the machine to get out any bits of thread
Clean the threading route with dental floss
Try adjusting the (automatic) tension
Threading according to the manual (with presser foot down)
Threading according to popular wisdom (presser foot up)
It took me several days to get through it all - I got fed up quite easily, and suffered from CBA (can't be
I keep looking at the fabric I cut out to make a wrap top, but I'm just not in the mood. I've got anearly-finished top on my dressform, waiting for me to finish the sleeves and hem, I just have no enthusiasm for it (despite getting a feeling of pride when I walk past it). I've got stacks of knit fabric to have a go at making some leggings, and I've got a pile of funky fabrics to make some lovely skirts to wear over the leggings.
I just can't get interested enough to even get started. Maybe it's the weather?
I'm going to have to go and buy some birthday cards, as I'm nearly out of time.