So, when using Ubuntu 16.04 or Xubuntu I started getting multiple prompts and pop up windows offering to set up Thunderbird, so many windows would open up that it would slow the system down and I could only log out or reboot.    Also similar pop up windows saying 'choose preferred application'.    Certain characters would type or not type such as '@' and the other ones on that part of the keyboard.    I was getting this strange behaviour even when using a live DVD.    Even stranger I was getting this even when I swapped back to a wired keyboard - I guess the Ubuntu system was trying to complete a task, on the installed system not a live DVD.   So I was getting really confused.     Then tried it in Windows 7 and got some strangeness - same thing with some keys not responding.

This keyboard has an email key right at the top so that was a clue I guess to the Thunderbird set up prompts.   That key is close to some of the other ones that were not responding.

Then I went to the Amazon reviews for this MK 270 keyboard and they were a bit mixed.    So I started to think I had a bad keyboard!   Searched Google for my problem and found nothing!

I even went out and bought a couple of new Sata cables thinking it might be some strange dodgy connector problem.    The new Sata cable worked perfectly just like the old one!!   And gave me the same Thunderbird issues.

Unfortunately, that day I had no new AAA batteries sitting around or I would have tried that sooner.     Needless to say  2 fresh AAA batteries restored things to normal.   And it has kept working perfectly for the next two weeks.