[PT user]

Hi
After a long day of sleuthing and some help from Digi tech support UK (thanks Dan), its been resolved. It turned out to be deeper than the Logic issue as core audio wasn't behaving itself and the Native card wouldn't work with the Mac at all except for with PT software. After uninstalling Pro Tools and installing the Avid core audio drivers still nothing, so I went back to my clean install system boot drive which was cloned a couple of weeks ago. Everything came back as it should be. Avid core audio drivers must have got corrupted. Its odd really as there were no system updates in between. I worked with the system on the back up drive and once satisfied I cloned it back to the main HD. Luckily all project files for all my apps reside on externals.

Thank you for your input - Im just posting results here in case any other users experience the same issue