Hudl 2 red light but not charging

[Guest cathud]

My Hudl 2 shows a red light when it is plugged into the mains; however it does not appear to be charging, as the percentage is not increasing. I usually power it off when I am not using it so that there is nothing to drain the battery in the background while it is charging.  When I power it back on, the percentage has not altered.  I downloaded a battery widget which shows that it is plugged in, but is not showing a charging rate.  Occasionally it will suddenly come up with a reading, and currently shows 2 mins 13 seconds - which I assume means it is going to take this long to charge 1%.  Any movement of the Hudl and cable usually results in the reading vanishing.  I did a factory reset this morning as a member who replied to an earlier post suggested it would cure the charging problems; however, it has made no difference.  I still occasionally get the message I had before about "insufficient power to charge device" so I can only assume either the usb charging socket is faulty; the cable is faulty; or the charger is faulty.  I did not have any of these problems with the original operating system - it all started when I made the mistake of upgrading it to Lollipop.