cogging noise on the mamba max 9xl setup

well today sucked cause its been raining all day so no races today. Anyway back to the problem. i never blamed the esc. I definitley think its my radio controller thats the probloem. and you guys are right about leaving the am behind. well i guess thats mu next project to get a good radio controller. what would you guys recommend? i guess just a mid priced one would be great. I defintly think it could have been the radio interferance.