I have similar noises coming from my 2011 custom as well. I chalk it up to having the fairing and an exhaust that exits the rear of the bike allowing me to hear it.
I never notices it on my Rocker C but the 2 into 2 Big Radius pipes and cams made it tough to hear anything!
My indie says she sounds like she should and told me to ride her hard!!
2011 Vivid Black FLTRX, 107" Rev Perf, Zippers Thundermax AT, Roland Sands Speed 7 AC, Iron Aces iPhone holder, 8" KW, V&H Duals & Black Widows, DDM HIDs, ARC 6.5's, S.E. ported heads, 30 tooth frt sprocket.
You never see a Harley parked outside of a Psychiatrist’s office, now do you.....