VISA Lock Error Without Using VISA Locks

[RMowatt]

I am experiencing numerous VISA Lock Errors (-1073807345) on resources I haven't explicitly locked.  This is happening on TCPIP connections to keysight N6700 power supplies and keysight N5242 PNA fairly regularly.

I have simultaneous loops in the application communicating to the different instruments, using a sequencer of sorts to pipe commands one at a time to each of my various loops.

Has anyone seen the locking error pop before while not actually using the Lock and Unlock VIs?  This issue has gotten worse lately and it has come time to find the root cause.  My only thoughts are that it may have something to do with having NI MAX and Keysight Connection Expert both installed and possibly trying to "ping" these devices.  Every once in a while me sending commands and these "pings" may clash and cause the locking error.

Error reads as follows:

"Specified type of lock cannot be obtained, or specified operation cannot be performed, because the resource is locked. VISA error code -1073807345 (0xBFFF000F)"

We are using LabVIEW 2013

Thanks in advance!