I had this issue with one other game, Dark Souls, and it's a Windows 10 issue, works fine in Win8.

When I start Fallout 4, the intro music plays on the TV, as soon as the screen where you continue the game pops up the sound cuts to the PC.

Was hoping someone had some tips for me, I really hate using headsets.

It's a laptop with Nvidia GTX 960M + Intel HD Gfx

Soundcard Conexant HD

I market my TV as default for sound.

In the device manager it says , SAMSUNG Intel® Display Audio, this is the one that plays sounds to my tv i guess??

So if anyone can help me, id appreciate it.

It is a windows 10 thing, search google for "no sound over HDMI windows 10" may give you preview build answers but they work, had to do it with my tablet, rollback the realtek audio drivers, and bingo sound works again.

Are you steamlink streaming as well, that requires a fixed audio bitrate, a low one, I cannot remember if it is 12K or 24K bits.

Good luck, it is an easy fix though.

Fixed it, installed some old Intel graphics drivers for win8, from early 2014.

I never thought that would work on win10, but it did, and it solved it.