Can I set Symphony Desktop to Slave to an External Master Clock device?

Symphony Desktop must always be set as the Master Clock and cannot slave to an external master clock. This is because of a restriction in the USB protocol that requires USB audio devices to use internal clocking.

To deal with this, Apogee included a special Sample Rate Conversion feature for the Symphony Desktop's optical input. You can read more about it here: Optical Inputs on Symphony Desktop can accept any sample rate, doesn't care about clock source