9. What Bluetooth codecs does the M11 support? And how to switch the codec?
A: The M11 supports the HWA, LDAC, aptX-HD, aptX and SBC codec. The HWA codec needs to be switched in the FiiO Music settings, while the others can be switched in system Settings -> Audio ->Wireless playback quality. Also, kindly note that after switching the codec, you'll need to disconnect the Bluetooth and then reconnect to have the changes take effect.
How to use the Bluetooth transmitter function of the M11