Short answer: Nope. Long Answer: Not even kinda close to a way to do this, that hardware is locked down good. If you can brute force the key that locks the adb

Short answer: Nope. Long Answer: Not even kinda close to a way to do this, that hardware is locked down good. If you can brute force the key that locks the adb/fastboot then you have a chance. Some of the echo's run android, so you'd need to make Rasspy run on android for those versions of the echo. Alternatively, you'd have to find the versions of the echo that runs a proper linux flavor, you might have a chance there. If you really start messing with the operating system or system software, you have to make sure that you can access the mics in software. (some of) their mic array and ADC array feature FPGAs that handle audio manipulation, so you'd need drivers/whatever to interface with those.