Some would call it 'being twitchy,' but Echo had every reason to be aware of his surroundings whenever something changed. Again his shoulders square, hands and arms locking his blaster in position as soon as the filtered whistling picked up on his sensors and reached his ears.

Whistling. Not a threatening sound, not in the slightest. It was what threw him off once the Exo appeared in full view, being more human in nature than, let's say, a droid.

Well. Asking 'who's there' would be pointless since Cayde-6 was already here. The least he could do was keep the blaster pointed downward. There was also a telltale helmet-tilt when it came to the strange fruits and vegetables on display. "Cyananas?"