Safari - Video Playback, fast forward, incorrect video length and no audio

I've had this happen on two different MacBook Pros (but not my iMac), on both Catalina and Big Sur. I think it might have something to do with external monitors being attached.

In any case, while I can't *prevent* it from happening, the fix I just found on 9-to-5 Mac works perfectly for me.

Essentially, when you hit a video playing too fast, open up Activity Monitor.

Near the top there should be a "coreaudiod" process, using somewhere between 5-20% CPU, and with a "CPU Time" value in multiple hours. If you don't see it there immediately, you can use the "search" button in the toolbar to search for "coreaudiod". Verify that the CPU is non-negligible (ie, above 1%).

This is the culprit.

"coreaudiod" is a background service which handles audio on the Mac; because it is a background process, it is managed by the OS itself so if it "goes away" it will simply be restarted.

Okay, in Activity Monitor, click the "coreaudiod" process, then click the "X" in the toolbar, then "Force Quit" (in my experience with this issue a 'Quit' is simply ignored by coreaudiod when in this state, so 'Force Quit' is necessary). On a recent fast Mac it may look like nothing happened, but if you look closely the "CPU Time" column for "coreaudiod" is not in the seconds; this is because the service automatically restarted when it was killed.

After doing that, try playing your video again. If the problem you are having is the fairly common one I was having at least, this should have fixed things, without restarting your Mac.

Thanks for your help, guys. I have this issue too, almost every day. It affects YouTube videos and all QuickTime files, as well as iTunes videos. Basically everything video EXCEPT when played through VLC, which so far is my only workaround besides rebooting, which fixes it.

I've never seen coreaudiod in Activity Monitor. It isn't there now, and it doesn't appear when I open Quicktime player, so the 9-to-5-Mac suggestion hasn't helped me.

So either there's something going on that can cause this that has nothing to do with coreaudiod, or else there's a trick for making coreaudiod appear in Activity Monitor.

Thanks again! This is a frustrating issue for me, daily reboots are a huge pain.

Hey there azglim,

We'd like to help get YouTube videos to play smoothly in Safari, so let's start with some basics:

1. You have macOS 10.15 installed, but if you have a compatible model, the latest version is macOS 11.1. You can verify which version number is installed by clicking on the Apple logo at the top left corner of the screen, then on ‘About This Mac’. Here's how to first Back up your Mac with Time Machine, and afterwards, here's How to update the software on your Mac.
2. You can check for any Safari extensions installed and disable/remove them one at a time to test if the issue remains. You can find the ones installed by opening Safari, then going to Safari > Preferences > Extensions.
3. Another good idea is to clear the history in Safari. You can do this by opening Safari again, then going to Safari > Clear History > Clear All History, then tap on the 'Clear History' button.
4. If this only occurs while watching YouTube videos and no other video websites have an issue, it may be a good idea to contact YouTube support.

If you need more help after checking the above, we recommend reaching out to Apple Support here: Get Support

Have a good one!