Jetée

Is the problem solely isolated towards streaming videos (Flash) in your web browser of choice, or have you additionally noticed that your upload/download speeds have altered as well? (testing it out with any random program of interest you might like from Filehippo.com is a quick way to make sure.)

Pure speculation here, (as I don't really know what packets are/do either) but it might be a problem and/or shift with your provider's servers. Or... perhaps the youtube servers that are mainly dedicated towards your geographic area of the worldwide web are under increased strain, due to population, webhits, environmental factors, or whatever else might affect the hub in which is dedicated to making sure some sites stay running.

I've had this problem arise a few times over the years, but before I could fully investigate what the exact root of the disturbance was, I moved onto the next rodeo.
I'm very intrigued to see and help in whatever capacity I can to see if you can 'normalise' your video-viewing proclivities once more.

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As human beings, our greatness lies not so much in being able to remake the world (that is the myth of the Atomic Age) as in being able to remake ourselves.

—Mohandas K. Gandhi