One possibly relevant point: I’m on a German OS (Win7) which uses a comma as a decimal separator. In input fields like the ones shown below, I have to enter decimal numbers with a decimal point, but they are shown with a decimal comma. Don’t know how they are saved. Maybe this leads to confusion.
Also, these input fields behave weird on Windows (not on Android). When you change one of them, some others in the same row may lose their values.
And while you’re at it: Could you check your definition of a decibel? When I program a L/R to M/S transformation as described here:
and immediately transform back via L = 0.5 (M+S) and R = 0,5 (M-S), the two filters in succession should do nothing.
The factor 0.5 should translate to -6 dB as described in the cited page.
However, a “do nothing” filter L/R → M/S → L/R with this value leads to a reduction in volume. The volume remains unchanged – as it should – if I use -3 dB instead of -6 dB.
So maybe there is a factor 0.5 missing somewhere in the definition of a dB.