White lines between blocks in Edge

Hi, 

I've got a problem with white lines appearing above and below blocks in Rise when viewing the course in Microsoft Edge. They seem to flicker as you scroll through the course which doesn't look great and is quite distracting. Sometimes the lines are quite thick and sometimes they are quite thin, they vary in size as you scroll. This seems to be a recent problem as this wasn't happening when I first started creating these courses and it only seems to be happening in Edge. Google Chrome, Firefox and Safari seem to be working absolutely fine. 

The padding around image blocks is set to 'No padding' and I've set the background colour to the same colour as in the image just in case. It is also happening between multiple text blocks.

I've attached some screenshots showing a few of the places this is happening in the course. Some are in Edge which is where the problem lies and others are in Chrome to show you what it should look like.

Is this a browser issue or is there something I can do to fix this? Any help would be greatly appreciated. 

Thank you.