Meta Slider crops and than resizes

We got an ackward issue with the slider. We set up the slider to display over a size of 1100px by 400px. The images we provide are 1100px wide at least. In the advanced options we ticket off stretch. We disabled the image crop.

Howeever, if we now load the imageslider, the images getting resized to 640px and than pulled again up to 1100px, creating a very blurry image and not the high quality of the image we expected it to do.

We followed all the steps to fix this, displayed on your website, however, to no avail. I tried to disable the crop by applying a filter in the functions.php

function metaslider_disable_crop($cropped_url, $orig_url) {
    return $orig_url;
}
add_filter('metaslider_resized_image_url', 'metaslider_disable_crop', 10, 2);

But sadly the crop still works and it doesnt grab the original URL from the image. We just want to disable the crop function so the images are shown in the right format. Is there anyway we can fix this?

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