SFR 455880 Code review markups - lock object should be volatile to avoid
unlikely-but-horrible threading issues.  Lesson: let your constructor
finish before starting a new thread to operate on your object.
SFR 458159 Blocked thread prevents call hangup

Improve logging to be able to better diagnose this issue.  Add protective
code to prevent it happening again.  Hopefully
Merge branch 'master' into maccoreaudio