10 kudos points awarded for honesty and sharing @pauld 
I do exactly the same with my laptop, Windows does like to moan at me on a weekly basis and suggest I reboot it properlyā¦ I normally give in and let it have itās little momentā¦ really useful to know that for yourself this helpedā¦
Thank you for this.
Hi Paul,
My name is Jessie and I work in the Support Team at Udemy. Iād like to personally follow up and let you know that our engineering team is currently investigating this specific issue for you.
If itās not too much trouble, it would be great if you can write in to support@udemy.com so we can follow up when this issue is resolved or gather more information from you as necessary.
Thanks again for being a student on Udemy and please donāt hesitate to reach out to us if you need help with anything else.
Have been working with support on this as well. Have sent them some Javascript console screenshots - and it does appear to be a UI problem since I can reproduce on Chrome and Edge - and you know Edge has no extensions
Glad to know the team is working on it.
Yes i been having the exact same issues and been trying 3 different browsers Chrome, Firefox, and Edge. For me Firefox seems to run the longest before running into issues, however all 3 browser eventually halt the entire browser. I have done the refresh, clearing cache, turning off hardware acceleration, and restarting both the browsers and the computer. The best results for me have been after a computer restart but it doesnāt last more then a hour or two before it starts to act up again.
I stumbled across this today, it seemed quite useful.
https://www.google.com/chrome/cleanup-tool/
Might not solve the problems completely, but if it saves having to reboot etc?
Performance is also terrible here, CPU usage goes from avg of 35% to 65%+ when trying to watch videos on Udemy. With videos also frequently pausing as a result. Was fineā¦ well, usable, about a month or so ago where the only real performance problems were with the UI, now itās the videos too.
I am experiencing the same. Iāve cleared all the gubbins in Chrome etc but itās still terrible. I have just tried Edge instead, I never use it. Whilst it was a bit slow to open Edge itself and then be responsive, the Udemy video played back perfectly.
I tested it with the āWelcome to the courseā video (number 2) at the very beginning as I figured less/no one would be on that.
One thing I did notice earlier was very high IO on my main hard drive. Being that Norton has real time resources, as does Diskeeper and Backblaze - I wonder whether perhaps there may be some background activities going on which think the PC is idle when itās playing the videos as I am not using the mouse/keyboard etc and then kicks off these processes. I guessing that when Chrome is buffering there is some IO activity, not 100% sureā¦
Just tested Chrome again now, same video and monitoring task manager, disc activity is around 5% and itās playing fine.
Not sure whether itās related or not, but might be worth some form of checking/comparisonā¦
@Jessie_Udemy im also experiencing performance issues with the web page.
when clicking on the button that shows the course section list (Next to overview) i get some performance issues. its nearly impossible to scroll through the list because of extreme lag.
im using my notebook for udemy because its easier to watch the lectures on one separate screen while running unreal on my pc. but my notebook should be powerful enough for a webbrowser ;). looks like there is a lot of javascript running in the background running. processor is at 3ghz but only about 50% load on 1 core.
im using firefox 47. win10 64bit home.
on my pc it works fine (also firefox, win10 64bit pro)
Not sure what tech is being used, but I did a bit of trawling on the web earlier and found a couple of other websites doing similar online training (udacity <- is this is udemy under another badge? - and pluralsight I think it was called) - they had various people mentioning about video problems also. There was some feedback on one of the sites talking about the use of Silverlight because of HTML5ās video something or other not being reliable enough yetā¦ but I dont know how accurate/relevant/up to date this info wasā¦ most people here seem to have been experiencing the problems for a good month or moreā¦ just wondered whether Udemy could check with the developers (in house I assume) and see whats on the old change logā¦ might be that thereās something that ties in with all of the problemsā¦
Thanks for bringing this to my attention. This is a known issue that our engineering team is looking into and they have released a fix for, but unfortunately the site sluggishness in certain parts of the site still affects some students in specific environment.
Iāve relayed all the information youāve provided here to our engineering team, but in the future if you write in directly to us at support@udemy.com that would be incredibly helpful!
Thank you for your patience and cooperation as we work through this.
Hi guys!
Iāve also had this problem, and for me it was because of an ad blocker. I think that over 90% of you have one installed, so my advice for you (if you have one, of course), would be to set www.udemy.com as an exception, or simply pause it while you are viewing a course.
I hope this will help you
Jessie I experience this too, in the Blender course by Ben and Michael. I tried Chrome and Firefox and the videos are nearly unwatchable and pretty much crash my browsers. My computer has high end specs too so itās not that. I used incognito mode on Chrome as that was suggested and it helps some but it still reverts back to being sluggish after a short time.
This happens also while viewing the curriculum of the course. I click on section headers and it takes forever for them to expand and load. No other sites give me this kind performance issues.
Anyways just thought Iād post my experience and how itās hard for me to try to do the course.
Udemy site and video player were never this sluggish from my experience.
I noticed that the first time after opening the browser I visit udemy and start playing videos it works well. After a while it starts slowing down and becomes sluggish playing videos in 3 second steps as if it is buffering. Opening a new tab and trying other websites with videos such as youtube work perfectly.
My solution for the moment is closing the browser and opening it again, then pasting the lecture url in the address bar to go directly to it and continue. Annoying but at least seems to be a workaround.
I am trying to see where the problems come from. For you Windows users out there who have this problem, do you have Microsoft Visual Studio installed? It might be something about Silverlight
Yes, and Iād say most of us doāsince it is used in the Unreal course and parts of the Unity course.
I just checked my Firefox settingsāSilverlight plugin is set to āask to activateā, so that āshouldnātā be the problem.
For me disabling the ADBLOCKER worked perfectly fine! Thanks alot
Youāre welcome!