Not keeping settings for apps!

[pnumio]

I want to keep Quicktime always muted when opening and when selecting via Preview on Mac. Whenever I put the volume to zero in the settings. Open quicktime its always on full volume. I can open QT, set the volume in Background music to zero and it works but i have to keep quicktime open. If i close the app and re-open a file its back to default setting and not at zero!?!