Thanks, brucek.
By careful adjustment of level I have managed to improve my Soundcard calibration. I have reduced the Live! mixer to 2 speaker (rather than 5.1) and set input to Line-in rather than default input. No effects. No bass or treble. The bass response is further extended but the ringing persists. This is with my two foot long cable using two solid RCA to mini-jack adapters. No other programs running except REW.
