Re-Render of jpeg with low compression

Ive been using Base Theme by ThemeZilla with your plugin for a while. I haven’t had the need to upload anything for a bi. But Ive just updated some new images here:

https://velvetsoup.co.uk/portfolio/business-in-the-community/

But now they seem blurry? My size has always been 960px wide and Ive have never had problems before. Why all of a sudden do the images look nothing like when I uploaded. No size changes, just the jpeg gets re-rendered on a very low compression.

Please help.

lister