Reply To: Techeiles 🔵❎🐌☑️🐟

Maybe you could dochek out of this by saying that even in the case where you only know one sound, the state of chiyuv that you remain in would only obligate you to blow the two other possibilities and lu yetzuyur you knew how to you would vadai be yotzei.

But even if you say that, you still have the problem that in various cases of safek kosher tefillin the halacha is that you wear them.