Im certainly not an expert, but I leave my kick in my
mod all the time and it never drains the battery. I can only think that there is either a short or something wrong with your MOds button discharging constantly. I dont know how a Phidias even looks, but contact the evolve people , hear they are really great to work with and maybe you and they can figure out why this happened.
I hope someone jumps in here with more experience with you particular
mod and can help you out.