I recently bought a Focusrite 6i6 audio adapter (2nd gen with USB2) for some voice over work direct to computer and noticed that it has an SPDIF optical input. I planned to replace my PCI-based Omega Claro II sound card with this but wondered if there was any benefit to keeping the internal sound card and connecting it to the Focusrite through the optical connector? Or would having both be more load on the CPU, latency, sound quality etc. Should I just replace the card and directly connect the Focusrite through USB? I'm using my PC for audio and video editing and have Yamaha HS7 monitors. Thanks.