Random Image Resizing Question

[xIsabel38]

Okay so this is a weird question, but does anyone happen to know why, when I rescale an image using GIMP, I get this weird line at the top and left:

It's not there when I check the original image against a black background.

Just wondering if anyone happens to know why this occurs and if there's a way to stop it from happening.

 

[BirdOPrey5]

I haven't used GIMP in a long time but does GIMP allow you to choose the resizing algorithm? (Bicubic/Bilinear/Pixel Resize/etc...) If so, does it happen with all of them?

 

[xIsabel38]

Not even sure, will check.