[A.C. SUBY]

i know i should post this in their forum, but i cant register for some reason, but i hope you guys dont mind answering a question mini z related, after owning an x mod for a couple weeks i decided to order a mini z. i want to know if this is normal? when i put the batteries into the car and turned it on, it started turning left and right and the wheels started turning, when i turned on the radio, it stopped but the car was noisy just sitting there without me running it. when i turn off the radio, the car acts funny again. whats the deal, did i get a bad car. the car runs fine with the radio commands.