Vizio M421VTT No Audio Issue

[Maverick923]

Hi,

I have a Vizio M421VT after much troubleshooting, I believe there audio on the mainboard to be faulty since there is no audio.

I have tried to power cycle, complete reset, checked mute, checked tv audio is set to on, connected audio out, and Bluetooth.

I hear something for a sec when flipping through channels with audio out connected to a small speaker. It sounds a lot like when flipping through radio stations very quickly.
I change channels and when I stop I hear something for a fraction of a second on the little speaker.

I have been trying to find a service manual for this tv, but I haven't had the luck to find any of the information I need.
I would not know where to begin trouble should anything audio on the component level.
Some help would greatly be appreciated.

[Maverick923]

Some help please. Perhaps a point in the right direction?