Hiya. I've recently been noticing something a little weird with the LSP Spectrum Analyzer in mid-side mode. There appears to be content shown that is not present in the normal stereo mode and I don't think should be part of the audio signal; what looks kinda like a noise floor or something. It's particularly visible in the high frequencies, but that might be partly because I have it set to a 4.5dB slope.
I wonder if sadko4u or anyone else can explain what's going on here, and whether it's a bug?
Below are two screenshots of the same sound source (a low-passed kick sample, so there shouldn't be much high content). The first is the one with mid-side enabled, the second without. Note the difference in the 2-20kHz region. (This is with LSP 1.2.15, clap version.)