Release Memory From Activity, Unreachable Objects

Release Memory From Activity, Unreachable Objects

I have an activity A that Calls activity B. Then when clicking (native
back) button A comes back (at this point B's onDestroy is called) I then
do this many times each time changing how B will appear (different text
etc). The issue is B is not being release from memory (which increases the
RAM total RAM starts around 30MB goes up 90MB~ after many clicks and never
going up or down from there) . After using MAT I find that activity B be
is being held by a context @ (android.media.AudioManager). I do not use
any media in the app, anyone know what this could be or any tips on how to
find out whats causing this. *This excludes Soft/weak references. I also
have this on my MAT report of Unreachable Objects could this be the issue,
if so how could the GC not collect it?