[Discuss-gnuradio] USRP and "fusb: (rd status -71) Protocol error"

[stevie.glass]

Hi

I've a rev 3 USRP which has the Flex2400 and TVRX daughtercards installed.
At one time the setup worked well - altho I've let it lie a while. This
week I've swapped out a TVRX and replaced it with the DBSRX in
preparation for a new project.

When I run usrp_fft.py things are fine for a few moments but inevitably
the program crashes with:

fusb: (rd status -71) Protocol error

repeatedly written to the terminal. Similar story for usrp_oscope.py and
most other examples.

This occurs both when using the Debian packages (3.0.2-2). When using
the latest subversion build I sometimes (once in every 4 or 5 runs) get
the error during the test_usrp_standard_rx "installation" stage but
otherwise it works and produces results such as:

xfered 1.34e+08 bytes in 4.19 seconds.  3.2e+07 bytes/sec.  cpu time = 0.184
noverruns = 0

What is the "Protocol error" error caused by and how can I fix it?

Kind regards,

Steve