This can happen during a charging process (independent of the device) and does not necessarily indicate a defect. However, as soon as the batteries or the charger become really hot, please contact our customer service, if you have ordered it through us.
Thank you for your feedback, if you have a complaint, please contact our customer service directly :) However, it is not Digitec that makes the product, but the manufacturer. You must therefore contact the manufacturer directly to lodge your complaint.
For me, the indicator lights up blue when charging. After some time, when the charging is finished, the indicator stops glowing. I suspect this is the switch-off, but no guarantee.