For now it seems to be ok: here's what I did, not sure what, if anything changed but...
I changed the profile from Viera 2011 to Viera 2011 DTS
In device option I turned off the AR correct

If I understand AR correction - this should do the exact opposite of fixing the issue...

What is strange is that I only turned it on AFTER I started having AR issues - so it couldn't have been the cause, but maybe part of the fix?