Digital out setting to qutest

I have never used your streamer but as there are only two options just listen to the same track or the same musical passage back to back through each setting and let your ears decide.  Like you I would say that letting the Qutest do all of the conversion is best, the variable setting may be related to gain or conversion rates however your ears will tell which is best. 

Presumably this means your streamer has some means to amend the volume of playback directly (via an App?). Do you use this, or simply set the volume via your amp/pre-amp? If it's via your amp, I'#d have thought the obvious thing would be to set it to fixed. However, as BtB suggests, it'll be easy to try both to see which sounds better (if there is any difference).

You might also be able to use the variable output to match the volume level to any other sources you use.

There are two issues here, speaking as a fellow Qutest owner. You can pick a fixed or variable volume level from the streamer (as I can do with  my Bluesound Node) and you can alter the line out voltage from the Qutest. My preference, after testing, was to leave a fixed output from the streamer as that avoided unnecessary additional processing in the streamer, and then set a sensible output from the Qutest. Basically, only let the Qutest play with the digital stream, and then give the amplifier a sensible level signal to work on. I have a Naim 282, and modern 3V line outs are tolerable but at the expense of absurdly low volume travel. I prefer to give the amplifier 2V and give it more chance to stretch its legs. 

Bob the Builder posted:

I have never used your streamer but as there are only two options just listen to the same track or the same musical passage back to back through each setting and let your ears decide.  Like you I would say that letting the Qutest do all of the conversion is best, the variable setting may be related to gain or conversion rates however your ears will tell which is best. 

There are more than 2  options. There are also 3 other fixed options for 48khz, 96khz and 192khz output to a dac. But I am pretty sure these options require fixed khz conversion before reaching the qutest.

With passthrough fixed and variable, it should be (I am hoping) simply passing the digital information untouched through to the qutest. I am still unsure about the differences between fixed and variable passthrough.

EUREKA!! Thank you all, it is indeed to do with volume control on my novafidelity.

With passthrough fixed volume controls are bypassed and with variable, volume control is functional.

So passthrough fixed it is