(This issue mostly only affects KBM and controllers since with a guitar the strum up/down is in the complete opposite of each other, but in the same button)
So the issue consists in, when alternating between strum up and down, most of times it will result in a miss because the other strum button might be still being pressed
It is weird since the two buttons, while doing the same thing, should be unrelated to each other - and thats why theres two different keybinds instead of two buttons for the same keybind
It may sound a bit counter intuitive, however, after playing my whole life on PC with a KBM, I dont have this issue with other rhythm PC games, being different only in festival
unfortunately this bug is still present as of season 4 / v30.10