I'm having an issue with configurable product swatch on my category view page (in grid mode).

We are using image in 420px in our category page but the image that are automatically switch with the swatches sources are in 210x.

All the product images source are coming from the getProductImageFallbacks() function from the configurable swatch Core (Block/Catalog/Media/Js/Abstract.php)

But i am stuck on how to change the resolution there. Really looking for any advice on where to go from there.

Please note that i sadly cannot go the easy way with a css fix due to image quality.