I'm pretty sure it was intentional. There were some complaints that the original bike was too quiet, so Honda added some bark to the pipes, not unlike the sound of the 1800 Valkyrie.
There were several changes over the F6B's short 4 year life. The transmission was modified (in all Wings) to address ghost shifting, cruise control was added, and the paint was improved over the 'soft' paint on the original 2013 bikes.