Volume Limiter for android? Is there a way to limit volume with a parental passcode on android?  I know there are apps for limiting volume, but is there any way to secure those limits so a child cannot change them?
If you are on a tablet running recent version of Android OS (4.3 and above), you can create a restricted user profile for your child.  There you can simply disable access to the app which you used to limit the volume.

For older versions of Android OS on tablets and on phones (restricted profiles are disabled for phones even on latest Android OS versions,) you can try various "app protector" type of apps, that provide password-based mechanisms for restricting access to various installed apps.