Constant refreshing UI in high population areas

In high population area’s my UI keeps refreshing, this is all since the patch before the recent one.
It started when transmoging my character, then has got worse, I have to fly out of the high pop area’s to transmog my character.
I’ve just logged off because it’s become unplayable this morning.

I’ve removed all addons
upgraded my RAM to it’s maximum 32GB from 16GB
lowered my graphics settings etc etc

can’t be my internet as its wired and set at it’s fastest.
I’ve search around and some told me its an issue with the priest talents but I’ve changed things and it’s still the same.
I’m not sure what the next step is

would it be down to my i5 processor?

it is a known issue, for now it seems to work if you change to Direct11