Appreciate replies (even if I have hijacked the thread with my personal woes )
I'm using a Aardvark Direct Pro soundcard and a Peavey RQ2316 mixer... connected using XLR leads. There's no gain knob on the soundcard's breakout box, that's all controlled using software. The gain there is set at '0'.
Jeesh just had a thought whilst explaining this, if I'm using XLR leads to connect to the soundcard.... it might assume it's a microphone and naturally boost the gain. Maybe I need to RTFM again after all these years, but thanks MM for highlighting a problem I've just kinda ignored.