Having trouble palying some videos

We need to see what all is running, a report from this will not display any personal info...

EtreCheck is a FREE simple little diagnostic tool to display the important details of your system configuration and allow you to copy that information to the Clipboard. It is meant to be used with Apple Support Communities to help people help you with your Mac. It will not display any personal info.

https://www.etrecheck.com/

Thanks for Old Toad’s etrecheck instructions…

Slow iMac 2017 - Apple Community

Use the Note tool on the bottom of this editor's toolbar, as shown in the image, to copy and paste the output from EtreCheck. In a Reply before you click post, look for this to add longer texts...

Malware - Malware detected!!!

Malware:

Login Item: ~/Applications/BeAware.app

Reason: Malware name match

Besides getting rid of that...

Delete these files & restart...

~/Library/LaunchAgents/org.virtualbox.vboxwebsrv.plist

~/Library/LaunchAgents/com.adobe.ccxprocess.plist

~/Library/LaunchAgents/com.adobe.GC.Invoker-1.0.plist

/Library/LaunchAgents/com.teamviewer.teamviewer.plist

/Library/LaunchAgents/com.teamviewer.teamviewer_desktop.plist

/Library/LaunchDaemons/com.easeus.dataprotectbackup.plist

/Library/LaunchAgents/com.adobe.AdobeCreativeCloud.plist

/Library/LaunchDaemons/com.teamviewer.teamviewer_service.plist

~ tilde indicates your user library folder

Apple hid the Users' Library folders...

Method 1:

1 From the Finder, select the Go menu at top of the screen, and choose Go to Folder.

2 In the window that opens, enter ~/Library, and click Go.

They are online videos or local downloads? This makes a big difference. Also try to play the same video on another device to make sure this issue has nothing to do with the devices.

Great news my friend... now I'd run anther etrecheck report to be certain we caught everything. :)