Thiel Owners

So put a felt cloth on the flat space above the tweeter on the 3.6’s?

Try it. Send a PM for more detail.
TT

Tom - I have to admit I'm, um, baffled by your laminar launch baffle treatment suggestion. How would that be done with the 3.7?

As I mentioned, I don't have 3.7s. If I were testing them, I would find some music and/or test signal that reliably produce the problem. I would use a stethoscope to reliably hear it. I would then mount felt and test, then add UltraSuede and test. Etc. The process is slow and deliberate. There is room for other input such as internal wire rattling, etc. I saw a video that showed the driver wires fed through silicone tubing. Perhaps that's a culprit. It is interesting that more than one person has heard something similar. I don't know the answer, but I do register your experience. 

Tom - are you able to specify a track or two on that Rhino collection that produces the sizzle effect on your end? I'd like to hear how that plays on the 3.7. I just called it up on Qobuz...always liked Dolly's music...somehow, After the Gold Rush started playing right away...whoa...