There's no way to access the audio ICs from I2C or SPI on the BP? You might also need access to the PMIC to turn on the amplifiers, but most designs I've seen

There's no way to access the audio ICs from I2C or SPI on the BP? You might also need access to the PMIC to turn on the amplifiers, but most designs I've seen have access ports from both BP and AP. (This was on Motorola devices, Q and the EZX phones.)