Don't process EQ until the user actually changes an EQ value.  Saves
CPU for our many users who never touch the controls.
TESTED=hand tested, didn't hear popping when the changeover happens
Merge branch 'master' into eq-disable-until-used
Merge pull request #227 from ywwg/eq-disable-until-used

Don't process EQ until the user actually changes an EQ value.