the cop would have to be a real dick to call you on that and you could pretty easily beat the ticket because they need to have a decibal meter at hand and few do and I don't think any bov breaks the decibal level long enough to warrant it.
I suppose they could tack it on to an existing ticket while they have you there.
And many many police are getting better at knowing what things are.
I got nailed in newark, ca. and they were asking me what kind of brakes and brake lines I was running.....the lift on my cam....stuff like that. but strangely enough didn't find the nos lines which I had very very well hidden and wrote me up for legal parts? Go figure....didn't matter anyways...didn't submit the tickets so aftet a year they were drops...no points no problems.....that was my civic.
so yeah...I highly highly doubt you will have a problem.
Maybe somone could confirm but I think it would be a fix it ticket and in the 10 minutes it takes to swap the bov off you can find a cop to sign it off and pay the $10 bucks and put it back on 10 minutes later. But I am not sure if noise violations are fix its or not?