Relay input selector wiring help needed!

[zoranaudio]

Hello All!
Can some of us help me about wiring inside the box.
In my design I have 5 inputs RCA and one for output to the amplifier.
The distance between RCA and PCB with relays is about 4 to 5 cm, so what is the best cable to connect RCA's to the PCB (relay's) and how to achieve the whole grounding(metal chassis RCA ground and PCB ground.RCA connectors are isolated from the metal chassis, inputs and output.
Is it good to connect all RCA's grounds(left & right channel & output RCA with one simple strait wire which will go between left and right conn. of RCA( I think this is called bus grounding) and than what about the PCB ground and the metal case(box), or star grounding in one point???
Is it good to use shielded cables or winded twisted pair of wires, and how to where to connect shield of the cable?? on one end....
I hope that some body will help me and give me schematic of wiring inside the switch selector?
PS:BTW I am not sure if already exist schematic like my own which designed one month ago, All schematic I found on the internet uses A PIC controller or Logic circuits, but in my case I am just using just three small transistors to control one input( relay ), and the result is great...It works very fine, this tested with 3 inputs and now i am building with 5 inputs but is easy to add more inputs.
Also at the first time i have problems when push and also hold two or more buttons and than was possible to connect 2 or 3 inputs to the output!!!, but after I fixed that and now works great when you hold 2 or more buttons it is not possible to connect in the same time, just will turn on other relay and the previous will automatically turn of!!!, just using 3 transistors for one input.
I really want to know is similar schematic already exist, and of course I need suggestion for inside grounding and wiring.
Thank you in advice.

[zoranaudio]

Soon comes the images!
I'm gonna present and patent my input switch selector with no any "PIC" or logic cir., but the same features as all known selectors with momentary switches with led indication and also mute function.