RCA amp cables are not working

i have a 1000 watt amp and i hook it 2 my 2 "12's. well when i have the rca connectors connected to the inputs my subs are liking humming, so when i disconnect one of the rca connectors one of my subs start knocking while the other one dont work, while when i switch the connector to the other side the other sub knock and the other dont do anything. can anyone help me solve my problem with my rca connectors.

Is the RCA's connected correctly on the head unit end? (Red to red and white to white) Are the jacks on the HU inputs or outputs? And what the heck do you mean by "knocking"?

neva mind i fix the problem myself