I don't know. I'm pretty sure it's not Cuba, since they seem as pissed off about it and eager to get to the bottom of it as the US is and they have no reason to screw up a detente they just negotiated.
Beyond that... who knows?
I don't think its the Cuban government either. I think its a radical or something along those lines.
Annihilate animated/flash ads, and then we can begin discussion of turning off Adblock.