How do I set my headphone volume to always be the same as speaker volume

[Android Central Question]

So I switch between listening to audio through an auxiliary cable to a stereo, my phone's internal speaker, and my headphones a lot. However, the volumes at which I listen with each of these are very different. My problem is that, since my phone saves the last volume I used for my headphones separately from the volume of its internal speakers, sometimes I turn the volume all the way down before plugging in headphones, but I forget that the volume is going to revert back to whatever volume I was using the last time I plugged in. If I was plugged into the stereo in my car, chances are that the volume was way higher than I would want for headphones and my ears end up getting blasted. I just want one universal volume to be saved for headphones and my internal speakers, so that way, if I set my volume before plugging in, I'm going to get exactly what I had it set to and not some random volume setting from a couple days ago. The ironic thing is that this feature is supposed to help prevent people from damaging their hearing, but it's doing quite the opposite much of the time. If anyone knows a way to disable this I would greatly appreciate your input.

 

[Rukbat]

There's no provision for that. You can control the volume separately for media and phone, but not for earphone and speaker. (Earphone/stereo is going to be the same coming out of the phone because they both come from the same place, the earphone jack - but you can't set the volume differently depending on what's on the other end of the wire.)