photoshop shortcut wacom trouble

[bangalore_monkey]

So, i'll start by saying that i use two of the keys on my intuos 3 to adjust the size of my brush in photoshop.

up until recently, i was able to hold down either key and it would automatically scroll through each brush size. however, now i have to click for every single incremental change in brush size. this, of course, makes it very tedious and annoying to go from a very large to a very small brush quickly.

also, the keys that are the ps default for this operation (the brackets) still do it the way i was used to.

anyway, does anyone else have this problem, know how to fix it?