Recently the TV volume output of my Arc + Surrounds has been way higher than my TV's volume control bar would indicate.

It is such that when my TV volume is set to '1', it is actually pretty loud. Turning my TV one step down to '0' mutes the TV entirely. My TV volume goes up to 100. So now my TV goes from Mute to Loud to Very Loud to Apocalypse Loud.

This is a recent issue and I don't know what has changed. In the past I used to set my TV volume between 10-13 for casual watching, and 15-20 when I wanted loud audio. Occasionally when I really wanted to piss off my neighbours or impress my friends, I'd crank it to 20-25. 

My Music and TV Surrounds are set to 0. 

My volume limitter is off. 

I just want the TV output bar to better reflect the volume, and give me a some wiggle room on the low level. 

Is there a way to calibrate this?

Perhaps related- my turntable & Port audio has also been a lot LOWER recently.