best way to connect pc to dac

No, and it is perfectly fine the way it is. The only alternative is to bypass the laptop and use a separate streamer like, e.g., the Chromecast Audio, the Apple Airport Express or the Sonos Connect. These all have optical digital outputs, apart from the analogue outputs that use their internal DACs.

There are lots of options, limited only by your budget and desire/ability to tinker. You have the bare minimum setup and it can certainly be improved. The Computer Audiophile forums are a good place to discuss with folks who are open to these issues and have lots of experience. I went from a Windows laptop to a server to a better server, used different cables, added external signal improvement devices, and linear power supplies. Each was a substantial improvement to the sound. Streamers are also a possible route, and these can also vary from a simple basic setup to a more complex one, with similar sound quality improvements at each step.

+1 re the post from @jaybe 

There are also gadgets that are placed inline that claim to improve the USB signal by reducing jitter. Schiit Wyrd is a reasonably priced option for $99. As always, there are much more expensive options that reclock the signal and may improve the sound. With your current set up, at the minimum you should run your PC on battery and not on AC since the PC power supply adds a lot of measured noise to the signal.

@mswobo,

I am with @kalali. There are much better inexpensive options to stream music nowadays instead of relying on your laptop. Unless you’re willing to treat that USB signal with a external reclocker and isolate the noise, you’re better off starting with something like Bluesound Node 2. 

I don’t know your rest of the system, but you have a very decent DAC. All you need is a dedicated streamer and Node 2 will give you the convenient and easy ‘noise’ free streaming experience.  

If you do decide to go Node 2 route, I would suggest buy a Digital Coax cable to connect your DAC with Node 2. The Node 2 has a very decent internal DAC but it’s probably not as good as Brooklyn. 

I heard Empirical Audio sells a killer Digital Coax cable under $300. 

Hope this helps!