I've been using the HD192 for several years now with no problems. I'm experimenting with summing through a 24 track console and decided that it might be nice to have an extra 8 outputs to be used for things like buss returns for the reverbs and delays I'm using in a project.
So I hooked up the 1224. Clock is derived from the PCIe-424 card which both interfaces are connected to.
Sonar didn't recognize the 1224 during it's first boot, but did change the name of the HD192. It caught the presence of the 1224 after restarting Sonar the 2nd time, but playback kept stopping at intermittent times due to "Audio Dropout" both before and after assigning a single set of returns to the 1224.
This was on an existing project that had been completely assigned to the HD192 previously, and worked perfectly (no dropouts).
This project is 44.1 24 bit, and indicators on both MOTU interfaces are 44.1. I didn't restart the computer after hooking the firewire to the 1224. I suppose I will see this evening if that helps out.
Anyone had any experience with these MOTU interfaces using more than one of them simultaneously?