Okay then it's hard to say from here. If you have the same issue with different materials and printmodes, you now have fresh ink and you know nothing has changed in the settings or elsewhere when the issue started...
Thank you. After letting the device sit for the weekend I thought I would warm it up and try another print test and the machine started to print better (not quite perfect but better). Perhaps my last flushing of the inks wasn't quite enough and now it's starting to get into the new ink? Either way I'm going to look at purchasing new YM heads and have then on hand should the device not improve further.