An introductory comment, I have loud audible snap.
That being said, I completely reject the idea that it is categorically a bad thing.
I think there are two different noises, one is slippage, where you hear a softer sound. The other is a crisp pop. I think the critics who say it is slippage are correct to the former, and incorrect to the latter.
I talked to Ricky Wysocki a while back about this, and asked him his opinion. he said that he did not think it was a bad thing, and that most of the guys from tour have that sound at least sometimes. So, if it is bad, go tell all the 1025+ guys they suck.
I think the sound is determinative most of throwing style. It depends on when the acceleration starts, grip, hand size, dermatological concerns (dryness, roughness, oiliness, etc.) and other science related concepts.
I don't think it sufficiently affects spin, velocity, etc. I throw a Teebird 450+ consistently, with load audible snap. I am not unique in that respect, especially on the internet. If it negatively affects me, who cares.
I agree with all posts here that say you are stupid if you focus on the presence or lack of audible snap when considering form. It is a dead end, and instead focus on your fundamentals, efficiency, and ease of energy production.