I am using the free Litmus E-mail template to build a newsletter.

It happens that sometimes on some E-Mail clients the images are stretched vertically. It happens really sometimes.

I am sending this newsletter using Outlook 2016 and insert my HTML file as text.

Result is that the newsletter is properly displayed on major Clients (Apple Mail, Outlook, Gmail) but with Airmail and Blumail the images are streched.

Any suggestions?

Thanks :D