I've been running Keyence for some time myself and never had a problem and have never heard of anyone else having any problems until this one. If the spped control came from Ultimate, then take it back to them. There are several companys who import Keyence, so unless Schumacher was the importer, they won't be able to help much. Most likely, Ultimate imported the ESC themselves and they should be able to help you. Good luck...
Speed Passion Motors and ESCs