Swordfish 220a pro with Traxxas Spartan radio - full speed by itself

[Amisol]

Hello.

Product: Traxxas Spartan
Radio: original TQI (Traxxas)
Esc: Swordfish 220a pro
Batteries: Gens Ace 3s 5000 MAH (x 2)

Have tried the following:

Radio - held the buttons "set" and then "on". Then it starts flashing red.
Boat: Connected batteries and held the button on the reciever. One beep and both units light green.

Then I test the rudder with the radio. Works. Then suddenly begins motor at full speed by itself.
What is the reason?

Thanks for reply!

[boredom.is.me]

Did you set your endpoints? I don't know how the sword works, but EVERY esc I have ever used in all parts of the hobby has throttle endpoint calibration. Did you try reversing the signal? That's a common occurance when swapping surface esc's in my experience.