Hi Guys, I'm voting this just to see if anyone else has had or having issues with Youtube using Safari on a 2018 Mac MM. My set up: I'm on the latest OSX version 10.14.5 (but the problem was occurring on earlier versions too). I'm on the latest Safari Version 12.1.1. I'm using the MM onboard graphics. My display is a Samsung 34" Ultrawide QHD curved Thunderbolt 3 which defaults at 3440 x 1440. But due to the distance from where I sit I run it at 2560 x 1080. But I've tried it at the default resolution and it makes no difference. I connect it to the MM via Thunderbolt, with a certified Thunderbolt 3 cable. Now for the Youtube issues (of which, I get none if I switch to using Firefox): Videos playing as if in super fast forward mode (even Youtube adverts) and just speed through (with no sound) to the end. This doesn't happen on all video's but about 50% of the time. It especially happens if I click on the timeline to jump forward or back. I have to try and replay the video to get it to play normally. If I click the full screen option on Youtube, whilst Safari is not in full screen mode, the screen goes blank unless I move the mouse, then it temporarily comes back then goes blank again. Doesn't happen if I put Safari in full screen mode. I don't have any special settings in either Safari or Youtube, and there doesn't appear to be anything to tweak or change to sort this out. I would just stick to Firefox, but I'm a Apple guy (iPhone and iPad), so like the convenience of Safari's auto form filling when ordering stuff on the net. Also it seems to be a little less CPU and graphics hungry compared to FF.