Audio switcher for stage

OK
First Hi, my name is Rodrigue and I'm pretty new to Arduino stuff.
I learned about Arduino because of a new hobby, quadcopters. So learning about that wonderfull thing it came to my mind to make a audio switch for my band with the Arduino. So here's the project:

On stage each member have a mic that goes to the PA but some times we want to be able to speak to each other whit out having the sound coming out of the PA. So the solution is to have for everybody a switch that would route the mic out to a separated mixer that would feed only the in-hear system.
Those kind of switch existe but they are expensive because they have electronic system that mute the signal before switching to avoid glitch in the PA. It's actually simple but they sale those thing for about 150$ each.
I thought that this could be done very simply by programming the Arduino to control 2 switch with a delay between them to allow the signal to cut before switching the signal. With 4 input (4 momentary switch) and 8 relay (4 for cutting signal and 4 for switching signal) and a small programming i'm sure i can do a nice system out of one Arduino.
So it would cost basically one Arduino 4 switch and 8 relay and some sweet and headache but I love that kind of challenge.

For now I'm just talking about the project. I'm going to shop for relay to fulfill my needs and do some test.
But what do you guy thing about the project. I'm going to a challenge that is way to simple for a Arduino and i should convince the tree other guys to by the switch at 150$? Or I'm in the right path and my idea is not bad??

Thanks for your comments and sorry if I'm not very clear, english is not my first language.

I will do some drawing and post it later.

Rod

Here’s a drawing of what I was thinking:
So on input switch, Arduino would change relay #1 to the resistance of 100 homs, then switch relay #2 to B and put back the relay #1 to original position.

Rod

Switch Audio SC V2.pdf (24.2 KB)