Try different governors and disabling hot plug.
Thanks Shumash and Roland!
Went into the Adiutor app, >CPU Hotplug. (PiTA with the multiple taps, let me tell you...)
I did not see a setting to disable Hotplug so I ...
Turned off 'Touch Boost'
and it improved measurably, but still registered an occasional double-tap while typing.
Scrolling through YouTube listings is also much improved, couldn't use it last night.
Gov is on Smartmax, haven't tried anything else - yet... (wish to hell I understood this more thoroughly...)
I've got the CPU set to 1728MHz, 1782MHz seems to cause freezing on this tablet that is made up out of two busted up units.
***
EDIT *** 08-14 Friday Night
Had been going well for 24hrs or so.
Then Touch quit registering Friday night while watching Youtube videos on headphones. Kept having to turn the screen On/Off.
And then the sound quit working. Tried a couple of reboots.
Dropped the CPU down to 1500 but that didn't help either.
Brought it out to the desk this morning, rebooted twice, still no-go, reflashed SU again, then I had sound again.
{Scratching-Head}