hw:0,2 works for ffmpeg but not recordmydesktop

I have managed to get ffmpeg to screen capture with sound using hw:0,2 but the screen flickers.
I get quality video with recordmydesktop but no sound when I use hw:0,2 which is the same setting I use for ffmpeg.
why is there no sound in recordmydesktop when using hw:0,2 and ffmpeg records the sound when using the same setting of hw:0,2?
any suggestions or help appreciated.

apparently I don’t have line out on my audio connectors on the back of the computer!!
If I turn the volume down the sound goes away… a natural event.