I do in fact use background music to provide atmosphere for posts when I think it's helpful. For example, tavern music if the characters are in a tavern, etc.

In fact, I like to embed the video on my posts, not only because it makes the posts as mobile friendly as possible (I use my phone to access the guild a lot, but hate it when the music stops when I switch tabs) but also to break apart any post that I feel like is getting a bit too big.

So, not only I use music to set the tone of my posts but also to make them more comfortable to read visually (just like how I use images for this same purpose).