Youtube Lag

[anaxcrosswords]

Hello old friends. Not been around for yonks - life and all that - but back with a question.
My default browser has been Firefox for a long time. Then I started to get annoying lag on YouTube. Every 4 or 5 seconds, a micro-pause, maybe quarter of a second. It made videos irritating to watch, but those tiny pauses also added up to significant lag, especially when watching live streams. I ended up several minutes behind the live broadcast.
Because MS Edge was already installed, I switched to that. At first - fine. Then the pauses crept in again and it became just as bad as Firefox.
So I installed Chrome, fortuitously at the time I started my own live streams, and it was exceptionally good. Monitoring my own streams from PS4, I could go 6 or 7 hours and only have the standard 10-second lag. But guess what? The pauses are starting again.
I run Win 10. Firefox has the uBlock Origin plugin but nothing else of significance; Edge and Chrome haven't had anything at all added. The PC was brand new about a year ago and is a higher end model with plenty of RAM and similar necessary gubbins.
CCleaner does its job after every session, and SUPERAntiSpyware runs every night, so my system isn't clogged up with anything as far as I can tell.
Any suggestions?

[Old_Geezer]

Are other PCs, mobiles,tablets getting the same video pauses ? If so, it could be your connection.

Check with malwarebytes or equivilent. Or see if taskmaster identifies a resource hog.

[Buenchico]

My money's on your anti-virus software causing the problem (especially if it's Window Defender, although Norton and AVG have both been known to cause similar problems).

Try something else.

[HansUrbancka]

Can overuse of Ccleaner cause Browsers to lag on streaming Videos ?