There needs to be a record of this somewhere and that really probably include the github page for this but I thought I'd put it here too.

https://github.com/espressif/esp-idf/issues/1720

This is info on some params that need to be changed to enable playing audio at different sample rates out bluetooth on the ESP32 (for the ESP-IDF).

And yes, I still need to write up some more info, but here's the github link for the project incase I forgot: https://github.com/Hexum064/mp3-bt-sc-i2s-oled