I had similar problem a couple of years ago. My solution was a music fidelity v-dac with an apple airport express. Stream spotify over wifi to the airport and then from the airport optically into the v-dac and then into amp (an old audilolab A8000). I went with wifi as running a USB cable across the room from pc to amp was a non starter. USB over more than. 3m is not a good idea. For the money it sounds very nice similar to my old arcam cd player. u need a wee bit of software called airfoil to capture the stream.
I also use an iPod touch and a dock from richer sounds. Airfoil have an app the let’s the iPod accept the stream from the airfoil app on the pc. The dock is about £20 and the dac on the iPod sounds ok through a Denon pma250 (another old one) into a wee set of wharfdale diamonds.