Jplay is a Hoax
JRiver recommends that you uninstall Jplay. It adds a layer of sound processing that can degrade sound quality, performance, and stability.
You will achieve the best sound quality with JRiver alone.
The author of the foobar player agrees.
For his computeraudiophile.com blog, Mitchco tested JRiver Media Center and Jplay. Both produce measurably identical bitperfect output.
Archimago also found no benefit.
For a more detailed discussion, please visit the HydrogenAudio Forum.
To protect its customers, JRiver will remove forum posts that discuss Jplay. JRiver will not provide support for Media Center if Jplay is used.