Switching between MPD and Roon on the BDP has been hit-or-miss with the drop-down menu on the dashboard. Often when I switch from one to the other, the little pop-up on the lower-right tells me to "Check Services". When I do that, I see that the previous selected component is active.
Also, about 1/2 of the time, when I switch from MPD to Roon or vice-versa, the drop-down lists Shairport-Sync as the selected option (even though I didn't choose that one). This happens regardless of how careful I am with the mouse to click MPD or Roon Ready in the list of options.
This behavior is pretty consistent. I am using the current release (not a BETA):
S2.32 2017-02-13
Build: Manic Moose
MPD: 0.19.21 NEWS
Kernel: 3.16-0.bpo.2-486