I have never looked into it but I do know some TV's have hidden settinga that let you do this. They are used for hospitals, hotels etc. I did a quick search and found hits video. No idea if it works but there are a bunch of other ones out there.

https://youtu.be/9Xg_6W5Meqg

EDIT: try googling hotel mode and your tv if this doesn't work

You can sideload android apps. Find a volume limiting app (you might need to use a mouse to get to some settings). There are a few different options, just search volume limiter in the play store.

Here is one I found with a quick search:

Volume limiter

I have my Shield playing at 100% and then control volume through receiver. Would it be easier to do the same for you but control the volume only through your tv?