Display artefacts

I am seeing display artefacts in logmein.  This is making it hard to do UI design work.

The image below on the left is a zoomed in version of part of my display from the host. On the right is how it looks in the logmein client window. There are (what I assume to be) compression artefacts.

I have my logmein resolution settings on 1920x1080 - which is the resolution on both client and host monitors. I have colour quality on HD and I have also unchecked "Use display accelerator" in the host settings.

The host has 3 monitors and the client just one. Is there any way to get rid of these artefacts?
Thanks.