Need ideas / help

Im trying to make a digital volume control for my car, i found a digital volume control which is easy to do but want it so i can select the chanel 1, 2, 3 or 4 and adjust the volume or that chanel and also have a digital display for the volume for that chanel.
If anyone can help please do, with schematics or if you can help, i can pay money for help too,
Thanks
Stu

Why 4 channels? Are these speakers that you want to control? How much power?

What i want is for my car stereo system, i have 4 lines with left /r chan. so 8 chans total, but i want to control each line seperate, basically, i have a l/r line to a amp for my rear speakers, another l/r to a amp for my front speakers, another line l/r to amp and 12" sub and one more line l/r to another amp and sub.
I want a little lcd so i can select either rear/front/sub1/sub2 and be able to change the volume to that selection.

Any ideas.
Thanks

^^^^^^^ Bump