You may not have a problem. You may have a problem because they may decide that you don't need the machine on the flight, only at the destination, and, therefore, not exempt from usual carry-on limitations. Although the machine is about carry-on size, it could become much bigger if you use the manufacturer supplied box.
What I would do is to be prepared to forfeit your carry-on, except for a purse or briefcase (small personal item) and carry the machine as your main carry on or be prepared to check-in your main carry-on suitcase, if you choose to bring it to the gate.
There are two ways to approach it. Try to survive or assert what one believes to be their legal right and be firm (knowing there may be consequences). That is one's personal choice.
I would not check it in unless you feel you can get a replacement at the destination by the next day. Another possibility is to see if such machine can be rented in Florida
Last edited by Toshbaf; Jan 21, 2018 at 1:06 pm