actually i had this problem when making Q adjustments at very low levels

There were bugs in beta 11 with using the equalizer with fixed Q settings and locked L/R mode. One of the two channels would always have a Q of zero. If you use auto Q, there's not a problem, and if you use independent left/right values, there's not a problem.

I also think that any errors to the Q setting induced by the bug would be saved, and would continue to be present in beta 13 if you didn't go back and fix them under that software version.