Videos hang / freeze for a few seconds on Ubuntu 18.04

disabling hardware acceleration in chrome helped me, installing new kernel didn't

to resolve the issue, simply install kernel 4.3.0 and everything works as expected!

copy/paste the following to terminal:

cd /tmp/
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.3-wily/linux-headers-4.3.0-040300-generic_4.3.0-040300.201511020949_amd64.deb
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.3-wily/linux-headers-4.3.0-040300_4.3.0-040300.201511020949_all.deb
wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.3-wily/linux-image-4.3.0-040300-generic_4.3.0-040300.201511020949_amd64.deb
sudo dpkg -i *.deb

Run these commands and reboot, selecting kernel 4.3 in grub extended settings.

hope this helps, as it did for me.

best regards

I experienced frequent random freezing of a few seconds too and disabling hardware acceleration did nothing for me (also, I don't see how the browser's hardware acceleration can affect the random freezing in other software in OP's case).

The solution in my case was to disable Intel hyperthreading from the BIOS of my machine.