bits is bits

Bit's are bits and some sound like chit, so I guess bit's are bits. 

It's important to have a sufficiently resolving system before the difference in streaming sources becomes obvious. 

@nogaps 

+ 1

I’m an old guy with lots of recorded music. And streaming has increased the enjoyment of music tenfold. The ability,  on the fly explorer all sorts of new music, or old music, is just incredible. iI’s much easier to use a streamer and have access to millions of albums.

@grunge1000 The question should be, why don't identical files sound the same?  What you're saying is technically correct, but not in practical application.  The files alone don't produce/make or project actual music that is audible to your ears through your audio system.  It's just a file that's just sitting there.  It's the implementation of the file that makes it sound different sourced through various different sources, Streaming services, etc., who do not use identical equipment, engineering to covert the file into audible music.   Consider a CD a music file.  Play the same CD through 10 different CD players, or sources, and you'll get a different sound from the same CD just about every time.  Happy listening.        

@parkergetdean 

I admit, this is what I thought: the streamer sends "data" to the DAC. Its job is to receive data and pass it to the DAC. It's not changing stuff, validating stuff other than 01101 is 01101. Are you saying it varies? 

If we ignore using a DAC internal to the streamer, and focus on just passing the data stream to an external DAC, on the surface you would think it doesn't matter.  However in reality that is not true.  If you break down the path of the data from the network connection through the streamer:

1. Data is received by the streamer (TCPIP),
2. The data packets then have to be assembled back into proper order by the streamers digital interface using processors/software/firmware/buffer RAM, etc.
3. The data is then "restreamed" out to what we could call the "digital output buffer".
4. In the output buffer, the data is then processed into whatever transmission format selected... to optical light pulses (TOSLINK), SPIDIF connection, HDMI, etc.  (I'm leaving I2S out of this because it is a bit different.)

Steps 2 through 5 all require passing through different circuitry, integrated circuits, software, and possibly even DC amplifiers to boost the signal strength if needed.  While the data 1s and 0s remain intact, jitter and clock timing errors are ALWAYS introduced into the data stream. 

And thus the design of the streamer, components used, etc. can effect sound quality regardless if the 1s and 0s are the same.