Images get compressed after switching from wordpress.com to .org

After changing to www.remarpro.com, images I upload to my posts after looking fine for about a second suddenly seem to get compressed and become blurrier.

I’ve tried installing a plugin to disable image compression, I’ve tried changing themes, editing the functions.php to set jpegs to 100% quality (though it happens with pngs too), disabling new plugins, but no luck.

Is there any other possible cause for this other than images being compressed? I’m not sure what changed after switching to self-hosted.