I'm still running 10.6.8 at the moment. But this would get me to upgrade. Has it been made possible to aggregate a virtual device with a hardware device successfully? (eg. an Apogee Rosetta800 as master clock along with Soundflower) In 10.6, you can set the switches and check the boxes (resample, etc) but the bottom line is all devices in an aggregate MUST be clocked by word clock. That means you can't mix a hardware audio interface with a virtual device like Soundflower. You can check the boxes and start passing audio (it lets you) but you lose sync anywhere from 5 minutes to 1 hour later and need to restart Core Audio. I'm fully aware that this is only intended to work if you use only the built-in audio with virtual devices. This means no pro work or live sound work possible with such a configuration. Any chance this functionality has been added to 10.8? Would it even be possible without a physical word clock connection?