[js_nyc]

Hello everyone. Thanks for your possible solution suggestions. I have tried everything mentioned and still in the Pro Tools Playback Engine window, there is no HD Native Thunderbolt option. I checked the version of the HD Driver, which is current. I do not think he uninstalled the previous driver when upgrading, but the new driver usually writes over the previous version (unless specified). Anyway, the Microphone Permissions had been established when I checked. As far as I knew, the PT Aggregate I/O was only designed to work with the internal Audio card on the Mac. The Thunderbolt HD Native driver would have the sophistication to access the features on the Native card. So for the Inputs, it would have access to all 16 channels both in the Low Latency domain as well as Delay Compensation on the output side, when not recording or overdubbing. From what I recall when I was testing Pro Tools from the PT Aggregate I/O my client "altered", the Low Latency Monitoring option was not accessible. As today is Monday here, I would appreciate some additional advice and/or an AVID Moderator's input. Thanks again.