I'm not sure this is really a "bug," just a discovery of a setting that doesn't play well with one song.
I'm using version 6.32.
Under "Stereo Image," I have "Azimuth & Channel Delay" on, max 100, diff 2.00. Channel Delay Fake Stereo is 0.000 msec.
Under "Stereo Image / Flat Stereo" I have "Stereo Image Processing On" checked, phase 1.00, width 1.00, 100% max phase, 180 limit 0 angle, 0 stereo only.
"Stereo Boost On" is not checked, nor is "DIFF."
I had kept "Center Bass" checked, but I've discovered that when I play "Think Of Laura" by Christopher Cross from the CD "Cross Words - The Best Of Christopher Cross" through it with these settings, the bass "growls" and "gurgles." Originally I thought I had a bad file, but I replaced the file with a new lossless rip from the CD and the problems persisted.
It was only when I shut off "Center Bass" that the "grumbling" goes away.
It, and the entire "Stereo Image" section seem to be challenged by this recording. With it switched on, the recording seems to go a little out of phase (perhaps because of keyboards that were perhaps out of phase in the original recording). With all of it switched on, the guitar starts to sound REALLY strange in some parts, like "auto-tune" has been turned on or something.
This is the only song out of more than a thousand that I've ever found that has this issue... in fact, it's likely more than several thousand songs I've tested, as I have Stereo Tool as my default in Winamp on my personal computer for personal listening.
I don't know that anything can be done to improve this section to make it work better with this song, or if I can change the settings and get a better reaction from the processor when I play the song. For now, I've simply switched off the "Center Bass" option.
I understand this may have to be a "quirk" of the processor I have to live with, and if it's only one song out of thousands that it has problems with, I would still say it's an excellent processor!!!