I'm wondering how you cleaned out the bobbin area. Did you remove the needle plate to remove lint? I have a Bernina 1230 and stopped having it professionally cleaned years ago. I clean it thoroughly myself, including vacuuming when necessary. (I tape a straw to my vacuum's crevice tool so I can poke it around inside the machine.) With this type of fairly frequent cleaning, I can't imagine enough lint accumulating in my machine to require professional servicing.