[arch-general] Kernel 4.19 preventing Firefox from playing videos

Good evening, I have a very strange issue with kernel 4.19.1 With this kernel Firefox no longer plays any videos. It opens the page but the video wont play. It gets even worse when I open another tab. This will freeze Firefox though system load is ok. But I cannot kill Firefox, even logging off and on will keep it running in the background. Only way to stop it is a reboot and shutdown will take approx 10 to 15 mins for various stop jobs running. just downgraded to Kernel 4.18.19 and things are fine. I'm running Gnome on a Thinkpad X201. KR Frank