Streamer with variable digital output

Please allow me to reiterate. This is a Gan1 amp/power dac. It has a digital input only.  There are no analog inputs and there is no volume control. I am curious about the existence of streamers with variable digital ouput. Thanks.

Okay. Thank you for the help. 

My research tells me Allanblissett is correct. The streamers I investigated appear to have fixed level digital outputs. I don’t know if other responders know otherwise or didn’t read my post carefully. It's an unusual circumstance. 

Seeking clarity has made me more confused than ever. 🙂

Thanks Fuzztone for the helpful response and advice. 

Dean Palmer, I was curious about alternatives to the node. 

I appreciate the many varied replies here. In the end I conclude that the Bluesound Node is the only streamer guaranteed to work with the Gan1. I'm fine with that as I can't imagine doing much better for $1800 plus one's choice of speakers. 

Thanks, 

Dave

I am still not convinced that any of the streamers mentioned or recommended in this thread, other than the Node, have the VARIABLE DIGITALOUTPUT (not screaming just emphasizing) required by the GAN1. None of the documentation explicitly states that they do.