I've found the exact same issue. I test my internal Intel card and see 1000's of data packets on an OPN network. With my Atheros cards, (ALPHA, TP-LINK, etc...) I see almost no data. This wasn't the case in previous builds, but I can't seem to get quality data capture on Kali 2.0, Kali 2016.1. Something has gone wrong in the drivers for Atheros IMO. Have any of you found a resolution? Thanks.