New uploaded PNG incredibly Blurry in Design tool

[UlyssePixel]

I have a strange issue when I try to use new uploaded PNG image: they are very blurry in the design tool.

I tried to reupload a PNG I already use in a design; just with a new filename  the content is identical. When I change the file in my existing design (replacing v1 by v2 identical PNG) the design become very blurry; when I replace it again by the v1 copy of the image everything return to normal.

With original V1 PNG uploaded a few days ago:

with V2 uploaded today (same content and resolution as v1) :

Does anyone has an explantion and a solution to this issue ?

[UlyssePixel]

Oh, an even V1 in Zazzle tool look much more blurry then the original image on my PC (same file viewed with irfanview):

[UlyssePixel]

Thinks are getting worse. I also have the issue with the JPEG images now. All JPEG I upload since yesterday are very  very blurry when I try to create a product with these images. I dont have the issue when I used previously uploaded JPEG in a new product.

This make creation of products impossible. Please, Zazzle help on this issue.

I am the only one to have this kind of issue ?

[UlyssePixel]

Today, sharpness of images returned to normal; It was probably a temporary glitch in Zazzle.