Mark Collette added a comment - 10/Feb/11 11:56 PM The YUI slider does not internally store the exact value, as one might programmatically set on it. Instead it's designed to respond to user clicks, and so internally does calculations to resolve the value from the pixel location. So, if the range is greater than the pixel length of the slider, then the value ends up being a lossy conversion of value -> pixel -> calculated value. So when stepping by a fixed step value, you won't end up with the exact value you'd expect. If the range is grossly greater than the length, than the conversion rounding leads to the key presses doing nothing at all. So, it's an application error to have a range (which is the max minus the min), that is sufficiently greater that the length. That will mean that a large swath of valus map to a single pixel point. If that swath of values is greater than the stepping pixel amount, then the step can't get to the next pixel, and will be unresponsive. You can overcome this by having a large enough stepPercent. This is documented in the length and stepPercent properties on sliderEntry, as part of ICE-6337 .