It is certainly possible to wireshark it and know whether it is transmitting anything. You don't need anything to be open sourced.
Re:Amazon Echo
by spacefight on Friday November 07, 2014 @03:04AM
(#8571604)
Read this again, then you'll see what I ment:
"It could be an update check, or it could be the transmission of a new voice fingerprint."
Same shit with cellphones, I have to admit.