Stereo & Electronics - Help with new cd player

When i bought my car it already had an aftermarket amp and sub put in it connected to the factory monsoon stereo. I just got a cd player installed but i can't control my sub due to no jacks. What can i do to control my sub level?

your new cd player didn't come with any RCA outputs? Is that what your saying? Or are you trying to control the gain of the sub?

it came with rca outputs. But there are no connectors to plug into the outputs. I bought rca connectors and plugged it in to my amp and into the cd player and still could not control the sub level.