Problems with Audirvana connectivity

I have transferred 5 TB of hi-rez recordings to a WD My Book external HD which I play through my iMac using the 3.12.15 version of Audirvana.   It always takes a long time for the selected music to start playing and often I have to click on the selected track several times to get it started. Then very often, the music just stops playing and I have to reselect it.  When the music stops, I commonly get one or the other of these prompts: 

"Stopping audio device" or

"Error:  Unable to grab exclusive access"


Can anyone help me resolve this problem and get Audirvana to work correctly?  

I've had several problems with Audirvana over the last few years. Your best bet would be to email Audirvana directly. They've always gotten back to me within a reasonable time. Good luck!
the My Book looks like it is a backup solution. possibly there are settings that need to be turned on on My Book that allow it to be more than a backup, more of a NAS. i posit this as it seems like the objects on My Book are slow to stream, almost like a sub par network connection.