The Anedio has the WM8805 in the digital input section IIRC, which is known to be a bit "warm", so possibly this combo with the Sabre 32 produces good results. I noticed though that people with Sabre-based DACs tended often to own tube amps of some description. I wouldn't be surprised if this would have been a good DAC for me when I owned an Audiovalve RKV.
You actually don't need to add a separate digital input receiver with the Sabre DAC as the chip can do everything all-in-one and that seems to be the way to go based on the implementations of Twisted Pear. Curiously the same company is developing a new output stage with coupling caps, which is technically inferior to their current DC-coupled output stage, as a "better" companion to the Buffalo perhaps to warm up the sound a bit like you said. Still, the tonality of these DACs is very far from natural which is obvious on acoustics and that's my main gripe about them. I wish I could try more Sabre-based DACs to confirm whether this is truly a character of the DAC (I suspect it is) or isolated to the Buffaloes only.