Flashvideo stuttering, sound not in sync with video

Question

Can't help it: flashvideos are stuttering and the sound is not in sync with the video as the video/picture always is like a second late to the sound.
Tried Firefox, Safari, Google Chrome, even with older flashplayer-versions than 11.5.502.110 as it is now, cleared chache, enabled and disabled hardware acceleration, tested different cache memory size (flashplayer internal settings), with or without camera and microphone allowance, every time I get the same results in a choppy / stuttering video and no sync in picture / sound.
My System is as followed:
MacBook Pro early 2008
MacBookPro4,1
Intel Core 2 Duo
2,5 GHz
L2-Cache:    6 MB
RAM:    4 GB
Bus:    800 MHz
with a GeForce 8600M GT
PCIe-Bus
VRAM 512 MB
Internet-connection via cable at least with 5 Mbit/sec up to mostly around 20 Mbit/sec and a 802.11n WLAN (tried LAN cable too, same effect)
My OSX is Snow Leopard 10.6.8 and I want to stick with that one, I keep the browsers and the flashplugin always up to date and I am not using a lot of background programs when watching, just one firewall and the usual system processes as I can see in the activity monitor, not much of percentage in processor usage, maybe 2 to 5 in percent all together, talking only of the background usage.
The core / processor usage, when a flashmovie is running, is around 80 to 90 percent,
there is an amount of 45 or so GB harddrive space empty and
somewhat of 1,8 GB of RAM not in use.
The connection-quality as shown in, say the "nfl game pass" window is very good up to max.
Sometimes, when the internet isn't that fast and the connection drops, the picture gets worse and the sound too, but that occurs not very often, maybe once a day and mostly when starting a video. After 10 seconds or so the quality of the picture and sound is high like brilliant HD, cannot complain about that, but the stuttering and out of sync sound remains.
I  watch the flash videos at internal mac-book-pro monitor 1440x900 fullscreen, sometimes not fullscreen,
tried an external LCD Sony Bravia Full HD Monitor  via DVI to HDMI adapter too
and I am getting  always, with any kind of configuration, the same results in stuttering video with sound out of sync.
Did already read faq's and forums and it seems that this is an issue for a long time with very different computer-setups and browsers in various versions of the flash-player. Couldn't find anything in accordance, like same graphic cards or same internetconnections, browsers or else, yet, so it comes down to the flash player.
The issue with the stuttering video and no sync in sound and video occurs at any time of the day with different streams, live, archived - I also tried changing  the mac-system-flashplayer settings in different combinations with no change at all: stuttering video, no sync sound.
If there is any information else that you need, please let me know,
I hope you can help as this stuttering and async is getting quite annoying by now...
greez anyway, out of vienna, austria
thanx,
manfred

Answer 1

Hi Manfred,
When you have the high cpu, is hardware acceleration enabled?  You mentioned this occurs with all releases that you've tested, does this include 10.3 on Firefox?
Chris