Streamed music sounds awful in my system and I don't know why ....

@esarhaddon

This has nothing to do with bits. The bits arrive just fine.  The problem is ground noise and pre-processing of the bits.  Most media players do digital manipulatino of the signal to put it on the media bus, and then spit it out. Most also do some level manipulation, including digital volume control, which rob you of resolution. As numbers are multiplied (which is how volume control is achieved) there are remainders nad truncation's. You can very esily get down into 10-12 bits effective resolution.

It matters not if its a $10,000 gaming PC or a 10 year old core duo.  Same problem exists.

@itsjustme The raise a number of great points:

Basically it's all about the noise from a computer. Fighting is possible but for those who computers aren't their passion, it's not worth the fight. Get a low power single-purpose device with a simple OS and w/o a million processes running that aren't in support of audio(aka. a streamer).

Not to quibble but the other side of this statement:

They also have made it so that you cannot play your own local library unless you have an active broadband internet connection. 

That's so they can give you all the fantastic metadata, artist links, biographies etc. For any victims who've ripped CDs in iTunes and lost album art...well Roon is your savior. I'm sure if enough people complain about it, Roon will provide an option to turn off internet connection required, but IMHE, it's a benefit even when listening to my own library. More often than not, their metadata and supplements are better than what's on the files. YMMV Cheers,

Spencer

On the quibble, i understand that they enhance music with metadata (however, its not as great as they claim - not i'm a user since pretty much day #1) but there is no enhancement when my music does not play at all.  Sure, give me the full experience with internet, but don't block the core of my system.

I have already complained, as have many more, and note they slammed the door on it ever changing.  So the answer as you say is "enough people"....apparently not enough today.  So buyer beware.

Anyway - to the OP. Figure out the exact configuration that you are streaming. Its often hard ot find in a PC.  Next, isolate. Even my roon core is run on a custom, linear, low noise power supply of my own design.  beyond most peole's ability, but buying one is just a few $100.

Don't just react to "PC bad".  PC not bad, PC just opens pandora's box.

Excellent sounding streaming can be achieved with your PC in the right circumstances. If using USB, make sure your DAC has a good USB implementation and has Galvanic isolation. I’m streaming through Roon and Tidal/Qobuz and upsampling PCM as High as 1024X DSD with my Audio Holo May KTE DAC and HQPlayer. Even without using upsampling, it sounds excellent. You don’t necessarily need a dedicated streamer to achieve excellent streaming results! People who are telling you the PC is bad just haven't hear a well setup PC that had good results.

“Excellent sounding streaming can be achieved with your PC”
@willywonka 

What dedicated streamer have you auditioned and compared with your PC to arrive at your subjective opinion?