I discovered what I thought was a bug with the latest version (1.23) of LOG4OM. I posted the info below in their support forum. Another Flex user was also able to duplicate it, but it seems to only occur with Flex 6000 series.
If I select "Settings", "Options", and any of the menus, upon returning to the logging mode, I lose all CAT communications. Shutting LOG4OM down and restarting restores proper operation. Happens every time.
LOG4OM developers seem to think its Flex related.http://forum.log4om.com/viewtopic.php?f=6&t=1868&p=10995#p10995