Error queuing message - Cannot execute as the database principal because the principal "dbo" does not exist

CREATE QUEUE dbo.MyAuditQueue WITH STATUS=ON
,ACTIVATION
(
STATUS = OFF
,MAX_QUEUE_READERS = 1
,PROCEDURE_NAME = [MyAuditMessageDequeue]
,EXECUTE AS OWNER
)

Created a new service broker queue and tried to send it a message.  Ran a profiler trace to see what was going wrong and noticed this error message in profiler:

"An exception occurred while enqueueing a message in the target queue. Error: 15517, State: 1. Cannot execute as the database principal because the principal "dbo" does not exist, this type of principal cannot be impersonated, or you do not have permission."

What am I doing wrong?

Service Broker 2014