My recommendation would be to contact Rostra, Tech service. There a gentleman that works there named Thomas, who seems to be very competent on trouble shooting their units; Note we have installed multiple cruise control units; every thing from Audiovox to Rostra to Equiis; and it is not uncommon to recieve a back dash mount switch, which can cause all kinds of funky stuff to occur.

Tech Service;1-910-277-1828