Failed Push Button Breaker?

[Knot Waiting]

I should know the answer to this already but I'm so frustrated I want to poll the knowledge of all you other marine sparky's.
I installed a huge, elaborate, new new audio system a few years back. All overdone for the marine environment. Then ran the head unit remote power to the existing "Stereo" on/off toggle at the helm.
Out of the blue she stops working. Switch won't light up, no power to the headunit. All wiring looks good. All inline fuses intact.
Question is. Even though the old OEM push button breaker on the helm never tripped. Can it just fail? It's wired in by Sea Ray so strangely that I can't isolate it out.
Thanks!

 

[thumpar]

If you are talking about the big breaker with the red button it would not just take out the stereo.

 

[Knot Waiting]

Nope, the small one specifically for the Stereo on the OEM switch pannel installed at the helm.

 

[Bondo]

Ayuh,.... Meter the wires on the back of it, 'n you'll know,.....

 

[Glaspar_Fan]

Car and Boat audio systems usually include an inline fuse. Have you looked for that? It would be bad form to wire an accessory like that direct to the main breaker without a fuse.