Do any of those adaptors support full 44.1 kHz I2S audio?
I've got collaborators who are selling my hearing aid thing as Tympan (http://tympan.org). All versions of Tympan have Bluetooth, but it has different capabilities depending upon the version of Tympan. Rev C is just a serial link allowing non-audio data the be exchanged with the Tympan. Rev D (to be released soon) has a more powerful BT module that allows for both the serial link as well as a BT audio link.
RN52 seems (after a quick glance onto the data sheet) to support 16bit@44.1kS/s I2S
On the Tympan D with the BC127, you can talk to it digitally like a Bluetooth classic device, but for Bluetooth audio, we did not connect it to the I2S bus. Instead, we chose to connect the analog audio I/O of the BC127 to spare analog I/O on our audio interface to the Teensy (we use a AIC3206).
So, while some might not like the fact that we don't have the digital audio coming from the BC127, you do get the flexibility of the analog MUX'ing at the front of the AIC3206. The MUX'ing means that you can do Bluetooth Audio, ambient audio, line-in, mics, or any combination thereof. I think that that's pretty cool. My opinion. (But, of course, I'm biased )
Chip
The down side of using the BT->I2S>Teensy is that this method would require either TDM or another I2S line (more pins). The TLV does have TDM so one half of the equation is there. However, it doesn't appear that the BT127 has TDM so it would take up it's own I2S line. I'm now wondering about this for my project... The Bluetooth transceiver takes up an entire I2S line unless I can find one with TDM. Ouch! That's 16 channels of TDM taken by 1 device!
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