Before ordering a new foot pedal. Take your machine in and ask to borrow one of theirs. If it hesitates, then it is the machine. Also, depending on where the foot pedal has been ( in a home with cats, dogs, or lots of sewing) there could be fuzz, pet hair etc inside the pedal. This has happened to alot of Janome owners as well. Be for warned the foot pedals are not cheap. My husband took mine apart, being careful to watch the sequence) and found carpet fuzz in it.
Cleaned it, works great.,
D in TX