I'm quite happy with the way RB opens at 100%. My headphone volume is controlled by the uphoria interface and i don't need to play with RB settings. If it suddenly starts at 50% i'd wonder why my songs went quiet. Or are you asking that your personal settings - master volume at 50% - should carry over from session to session or when you update? that doesn't seem unreasonable if you can't control the volume any other way.