Embedded YouTube video play button blacked out

[alicegenie]

Help! I've been able to successfully add YouTube videos to my product pages and they play fine but where the red YouTube play button usually shows in the middle of the thumbnail, is just a black circle. I've tried reloading the video to YouTube, uploading a new thumbmail of the correct ratio (16:9) but nothing is working. You can see the issue on my webpage here - https://planninggenie.co.uk/products/extending-your-home

Can anyone help?