Noise Under Hood

[PSSST]

I have a 2016 EB Premium with the FP CAI and tune. I'm hearing a single "pop" noise coming from under my hood. It seems to happen when I let off the gas and the boost drops and goes into the negative side. I also can hear this sitting still in my driveway after revving the engine, I will hear it shortly after it returns to idle. It almost sounds as if there is a check valve closing or something. Has anyone else heard this under their hood?

Any input would be greatly appreciated!

 

[Willie2]

BOV?