Hi,
What is your 12V 2A supply?
What are your brushless motors? spec etc..
A brushless motor will have an electronic control system on board and may be putting high frequency noise on your 12V supply line.
Tom... 
Hi,
What is your 12V 2A supply?
What are your brushless motors? spec etc..
A brushless motor will have an electronic control system on board and may be putting high frequency noise on your 12V supply line.
Tom...