Hi again! While setting up a pair of SVS SB2000 subs in the listening room, of course I made a little playlist to examine the low end. This is how I found what might be the bass splat Tom described on 4/15 above. Somewhere I saw Boz Scaggs "Thanks to You" suggested and this audio example (recorded with my iphone) documents the noise coming from my right CS2.2 - no subwoofers, no left channel, from about 10 inches away. You can hear it at 8-11 seconds and again 22-24 seconds.
For reference, the Decibel X iphone app reported 60dB spl as measured 1 meter from the speaker during the splat. If I play it any softer, then the noise goes away and I never heard it on the left speaker.
So now I'm interested in the XO solution when it becomes available, even though my normal listening never revealed this noise before. I guess now I'm suspicious.