I really think I found the solution to the PBX stutter. It was related to my Bitdefender Security suite, but NOT the AV. Turned out to be the "Advanced threat defense" function of the security suite. Apparently this function saw PBX as a threat and was somehow impacting its performance and causing the stutter. When I disabled the "Advanced threat defense". Stutter was REALLY gone as far as I can tell. Re-activate it, stutter freaking city man.
Thankfully, there was a feature in the ADT do add the PBX and VP executables to a white list, and that is allowing the ATD to remain active to do its normal of preventing hi-jacks and other bad stuff. Back when I was troubleshooting this weeks ago, I deactivated the AV, but not the ATD. Wish I had...obviously.
So I have a very high confidence that the issue is now resolved. I will report back in a week to hopefully, declare it completely resolved. Thanks again to everyone who chimed in to help.
-B