My Brother machine would quit sewing altogether at one workshop. It would start sewing then just quit. I about pulled my hair out. At home that very night it sewed perfectly. DH said if my machine was in a power strip with a lot of other machines all going to one plug then my machine was not getting enough power. ? It is a high speed Brother so maybe that was the reason. No breaker tripped at all but he stands by the not enough power thing.