CAT control of FT-920

I couldn't find an appropriate transistor to control the PTT on the FT-920 from the serial port and I stumbled on the rigcltd pages on the Internet.

rigstld is a Linux rig control daemon and so I have spent a few days working out where to add the code into wspr.py.
It's quite straightforward, only about 8 new lines, and now I have the PTT controlled through the CAT port without any messing around with a soldering iron(!)

However, occasionally I am getting this error:

Expression '*odev = open( odevName, flags )' failed in 'src/hostapi/oss/pa_unix_oss.c', line: 821
Expression 'OpenDevices( idevName, odevName, &idev, &odev )' failed in 'src/hostapi/oss/pa_unix_oss.c', line: 864
Expression 'PaOssStream_Initialize( stream, inputParameters, outputParameters, streamCallback, userData, streamFlags, ossHostApi )' failed in 'src/hostapi/oss/pa_unix_oss.c', line: 1239
An error occured while using the portaudio stream
Error number: -9985
Error message: Device unavailable

but I am not sure if this is related to the CAT control I have added or a problem with the sound install on my system.

If anyone wants me to tell them the changes I have made for CAT control please contact me.