Unsharp mask and Smart Sharpen soften automatically. CS4

Hi everyone, thank god for this site as this problem is driving me crazy. Every time I apply either smart sharpen or unsharp mask, photoshop will automatically reduce the intensity of sharpness after I hit the OK button.
For example, I will get into the sharpen dialogue box, set the correct values, the picture looks fine at this point, then click OK. After that, photoshop will then reduce the level of sharpening I have added. I have no idea why it's blurring my sharpening but it's driving me mad. Does anyone know what's causing this?
I have both the 64-bit version and regular and it happens in both. Photoshop CS4, windows Vista.

check your advanced settings in either un-or sharpen filter is it set to high for the gaussian or lens blur?

I'll check that when I get home. I have noticed that the problem I'm seeing is most obvious when I sharpen while zoomed out to 25%. When I sharpen while at 100%, it doesn't seem to happen, or at least is far less noticeable. Thx for replying iDad.

rob4q2, My friend is having the same problem. Did doing unsharp mask at 100% zoom solve the problem completely? Or was it just less noticeable now? Did you find another way to work around this CS4 bug?