Horrible card image corurption

[Selena Ulrich]

Hi

In my current stack, I've got a routine that locks the screen, shrinks the
stack's size (from 679 pixels by 385, to 297 pixels by 420) then prints the
card, resets the size to the original, moves back to the original card, and
unlocks the screen. Unfortunately, when the screen is resized, horrible
black lines are left on the tabbed button I have on the first card that I
cannot easily get rid off.

Can anyone suggest how I can avoid getting these?

TIA

Selena