So it was the Micro SD card
As usual when things don't work with HC2 (with those other SBC that are equipped with Micro USB to be powered with also the usual undervoltage dilemma might be the culprit). If I were you I would buy two good A1 rated 16GB SD cards immediately to use them in a rotated fashion (easing offline OS backups)
First one was a 16GB Kingston
Most probably not but a fake card. All the popular brands are loved by fraudsters who print those logos on their counterfeit flash products. That's why testing SD cards prior to usage is that important...
