Dutch & Dutch 8c with multiple sources

Simple selector switch. Remote for convenience.

I sold the D&D 8c but I always used all digital AES3 to the speakers but for what you want you'll need a preamp or DAC with multiple inputs.  

I don’t want to introduce another dac into the system. Can someone please tell me the names of a few preamps that would work?

I do not think there are any hifi preamps that take two or more toslink inputs and have an aes3 output. Or do I misunderstand how to do this?

That's why I said you might need to use a preamp or DAC with multiple inputs and use analog output to the speakers. The way I did it was setup my server on the network and used a Lumin U1 mini to stream from my ripped files and Quboz to the speakers.