Lights Dimmer Switch controls Radio Volume

I have a 98 Century Custom that my CD player went bad on, so I bought another one off Ebay that had the same matching #'s and was made for my year and so on, Now that I have installed it here is whats going on........

The volume switch does not work
The volume stays on real low until either you turn the headlights on, or when they come on automatically at night
And today I realized the dimmer part of the headlights will adjust the volume

What the heck is going on here??????

Hopefully someone can help me with this ET of a problem.
Thanks so much

I have a 98 Century Custom that my CD player went bad on, so I bought another one off Ebay that had the same matching #'s and was made for my year and so on, Now that I have installed it here is whats going on........

The volume switch does not work
The volume stays on real low until either you turn the headlights on, or when they come on automatically at night
And today I realized the dimmer part of the headlights will adjust the volume

What the heck is going on here??????

Hopefully someone can help me with this ET of a problem.
Thanks so much
i think you have your dimmer power, switched with the deck power,
switch the power lines back and it should solve your problem.

Is there by chance a web site that would tell me which two wires by color I need to switch?