Finding a headset microphone compatible with the BTR5-2021

The only time I’ve gotten the FiiO BTR5-2021 to work with a headset mic, it’s been the Sennheiser PC38X. I tried the mic that came with the Philips SPH9600RM, nothing. I just tried a V-Moda BoomPro (which has its own issues, like, the impedance I measure on the left and right channels is way higher than it should be, and if you don’t get the inline volume control just right, the left channel is significantly louder than the right), same thing. Reached out to V-Moda support. Really frustrated so far...

Update: I picked up. another PC38X (now branded EPOS, after the Sennheiser spin-off) on sale for $129 (from $169), and picked up the Boom Mic for Drop + THX Panda Headphones ($9 instead of a purported list price of $49). Both work perfectly with the BTR5, and the boom mic fits the SPH9600 perfectly. Huzzah.

Drop Boom Mic

 I wish I knew why the BTR5 seems so finicky when it comes to which microphones it will work with. Also, the BTR3 is a less expensive module that will do what the BTR5 will vis-à-vis converting a wired headset to wireless (at least for my relatively pedestrian purposes), but is apparently even more particular about what it will work with (one redditor writes: “The problem is, not many CTIA cables with microphones are compatible with BTR3K ... You can find many reviews which complain about that.”)

At any rate, I finally have a solution to my open-backed wireless headset requirement (two, in fact), and that’s good enough for me.