[Darryl Ramm]

Uncheck "ignore errors" while troubleshooting. It will mask/hinder solving any problems. You hopefully will get a DAE error then instead of clicks and pops... then solve for thats DAE error.

It's a fresh pro tools install? What does that mean?

Were there any past Pro Tools installs? Or any third party plugins you have installed for for other DAWs? They will often install .aaxplugin files which any new Pro Tools install will just load. If there is any possibility of this you should do the test or moving all .aaxplugin files out of the plugin folder and let Pro Tools put back the default plugins.

Pay attention to all the usual Windows optimization things, double check you have done all of them, including all the BIOS settings, cstate etc., then especially do the CPU priority and affinity tweeks which are not usually on the Avid optimization lists but are well discussed on DUC recently.

You are not trying to run at a very high sample rate are you?