I have reports of a slight carrier when operating on SSB. Checked my second rig and sure enough, it's there. I'm running a Flex 6300, SSDR 126.96.36.199 under Windows 8.1. The locals who have reported it say that this is something new, perhaps with the latest release of SSDR.
I have converted this topic to a support HelpDesk ticket (http://helpdesk.flexradio.com) for expedited issue resolution. If anyone else is experiencing an issue similar to this one, please submit a HelpDesk support ticket for issue resolution.