Scroll bar gives wrong values

[StanSz]

I have a scroll bar that I have set up to have a range of 0 to 1000 with a small move of 1 and a large move of 25.

When I click on the scroll bar I am getting the wrong values. Here's an actual sequence of clicks

Start at 509:

Small Up = 519..... +10
Small Dn = 510..... -9
Small Dn = 502..... -8
Small Dn = 495..... -7
Small Up = 503..... +8
Large Up = 653..... +150
Large Up = 803..... +150
Large Dn = 653..... -150
Large DN = 503..... -150
Small Up = 508..... +5
Small Up = 516..... +8

I've checked and the Small value is set to 1, and the large value is set to 25. At least the large move is consistent at 150 (6 x the set value), but the small move is moving around.

At one time this was working, but I can't imagine what I might have done to alter it.

Anyone have any idea what's causing the wrong values to be given ??

Thanks

StanSz