I have an idea for an audio product what should I do?

Agree with @carlsbad.

You need to build it, demonstrate it and then patent it if the feedback is good.

I'm guessing that it's some kind of bespoke networked active system.

Sometimes it is possible to find a niche in the market that the majors can't risk gambling R&D and tooling costs, but as you can imagine, it's never going to be easy.

It took Roy Gandy (Rega) many years of designing Rega Planar 3 prototypes (+ a hefty redundancy cheque from Ford, I think), before his idea took off.

If you were to contact an existing manufacturer, Rega might not be a bad place to start.

Thanks for the detailed post Kenjit.

Construction will start tomorrow on one of my least used tennis courts (located far beyond the stables).

DeKay

Kickstarter has a cool program 

Kick starter works good sometimes 

It didn't get the battery powered ESL headphones off the ground.

@dekay Careful building one to sell.

I doubt if Kenjit did a proper patent search.