Punchblock::Event::Complete event bubbling

I have a situation where I need to know when an asynchronous playback successfully completes.  The call to `call_controller#output` returns a `Punchblock::Component::Output` object, which should trigger a `Punchblock::Event::Complete` event upon completion.  When I register an event handler, it does not fire.

I traced the problem down to another area where the `Complete` event is handled and is being swallowed rather than continuing to bubble, which appears to be incorrect.  Adding a `throw :pass` in the event handler resolved the issue.