When opening JuK the volume level is sometimes set to "-2.147.483.648%", while the actual volume is unchanged. This issue can be resolved by clicking on the volume slider, in which case it returns to a value between 0-100%, with the actual volume increasing/decreasing.
Dear Maintainer, The volume indicator and slider **always** shows wrong volume level (-2,147,483,648%, equivalent to 0x80000000 in int32_t). The problem didn't affect actual volume level, and i could still change the actual volume by swipe the slider(but -2,147,483,648% will appears again on next time).