Thanks to 'phisher king' for this very informative post..
Flashplayer to v10.1 Stutter Bug:
Despite the almost total lack of OS and specs information in posts, I've now had a bit of spare time to try to confirm what I believe to be the cause of the stutter problem associated with updating from earlier versions of Flashplayer to v10.1. As mentioned previously, it only affects my newer laptop, (which is running Windows 7). It's an Acer Timeline 4810TZ, with rather low clock speed and integrated Intel graphics, designed to give up to 10hrs battery life. Fine as a portable laptop for use on the train etc, but not ideal as a video streaming platform. I first had to eliminate a fairly common but unrelated problem which could otherwise have confused the issue. It was prone to memory leaks in the wmpnetwk.exe process when playing video, sometimes causing runaway CPU use. (I suggest others check this too, as if your graphics card/CPU is only just up to the job of playing TV Catch Up's H.264 video stream, this could push it over the edge). I disabled it, [Run > services.msc > Windows Media Player network sharing service > Properties > Disabled]. All my drivers are fully up to date and once the memory leak was cured, everything was working fine with v10.0. I then updated yet again to v10.1. The stutter problem immediately returned, (using Firefox v3.6.6). It doesn't matter which version of Firefox is used as it's not the source of the problem, although there are significant differences between pre-3.6.4 and later versions, I found stutter could be eliminated by using the low quality streaming option, (in beta and not available to all TV Catch Up users, apparently), indicating a graphics card overload problem.
Using Internet Explorer also cured the problem. However, Windows 7 contains its own H.264 video codec and doesn't rely on Adobe's Flashplayer. (Firefox can't/won't use this - see the link in my previous posts for a discussion of Mozilla''s open source policy and codec licences). Obviously this is of no help if you aren't running Windows 7, and personally, I hate having to use IE for anything anyway. Using SysInternal's Process Explorer to compare CPU usage between the latest and previous versions of Flashplayer showed - v10.0. ____ 65-40%/25-20% v10.1. ____ 85-60%/50-45% (The figures following the 'forward slash' relate to Firefox's plug-in container, as opposed to total percentage of CPU). Disabling hardware acceleration removed the stutter problem. It's necessary to close and then re-open the video stream window to make sure the change takes effect. With it enabled, it's sometimes not even possible to get the settings window to open when watching TV Catch Up, (H.264 video), as it locks up the system and even makes the browser difficult to close. It's necessary to go to another site using Flash, such as YouTube, to change the settings, and then return.
It's clear from all this that v10.1, (with it's new GPU off loading feature), works the CPU/graphics card a lot harder than previous versions, resulting in stutter if your PC's specs aren't up to it. I complained about this via "Contact us" on the Adobe website some time ago and suggested that they should, at the very least, make the last 10.0 version available for now, not just the 9.0 versions which are still available for those using older incompatible OSs. The more people complain the better, and they may bring out a better designed, less byte-hungry plug-in eventually. As there are security vulnerabilities in earlier versions of Flashplayer, (and doubtless in v10.1 as well; they just haven't been revealed yet), I'd advise Firefox users to install the free NoScript add-on. It blocks Flash content, (and Java script), by default until/unless you give permission to run on sites you trust. (It also protects against clearjacking and clickjacking exploits, so it's well worth the trouble).
If you are having problems with Flashplayer v10.1, try disabling hardware acceleration first. [Right click on any Flash video content, (try YouTube if TV Catch Up won't allow the settings panel to open), choose "Settings" then the display tab, (first icon on the left) and uncheck "Enable hardware acceleration"]. Alternatively, use system restore to take your PC settings back to a time before the update. (This is best done in "safe mode", although even then I've had problems in the past wiith some antivirus software databases becoming corrupted and had to use "Add/Remove programs" for the repair option, or even remove and re-install). I also recommend forcing the "standalone" install option wherever possible when updating plug-ins like Flashplayer, in order to get a copy of the executable. I have a backed up executable of v10.0.32 in case anyone needs a copy.