USRPN210 Calibration Problem

This question is directed to Josh B., but if anyone can comment, it
would be welcome:

I tried the calibration apps this evening on a B100 and a Rev3 N210.
See http://files.ettus.com/uhd_docs/manual/html/calibration.html

The B100 worked like a champ and all three calibration procedures
completed.

Unfortunately, when I tried the procedure on my N210, it failed,
reporting that the LO failed to lock in a timely manner. Output pasted
below:

spacequest@sq-macbp:~$ sudo /usr/local/bin/uhd_cal_rx_iq_balance
–verbose
linux; GNU C++ version 4.5.2; Boost_104200; UHD_003.004.000-7dc76db

Creating the usrp device with: …
– Opening a USRP2/N-Series device…
– Current recv frame size: 1472 bytes
– Current send frame size: 1472 bytes
Error: timed out waiting for TX and/or RX LO to lock

The N210 does work in flowgraphs and other applications and I have
verified that the lo locks in a flowgraph by probing the
get_dboard_sensor function.

I have a WBX in both units. I am running the very latest master of both
GR and UHD. Both units have the latest FPGA code and firmware.