Worked last week. iTunes works fine .
iMac running 10.11.4 El Cap Sound set to Ayre USB interface (this alone makes iTunes work)
JRiver 21.0.77
Options
Audio Device set to Ayre USB Interface
Device opne in exclusive access and Integer mode
DSP output format to DSD in Dop format
all sample rates set to no change.
J River plays to nothing comes through on the USB port. Again iTunes works.
Why is J River so fragil? I can't play any format ie flac, aiff, w4w, DSD etc.
Again the computer and external Ayre Codex plays just fine in iTunes.