skype and msn messenger voice messaging connection stuttering

[#1]

I have been trying to get either skype or MSN messenger to work for making either voice or video calls.  it is basically un-usable due to the delay and stuttering.
Do Plusnet actively block these types of connections?
Is it due to my region and the exchange here? (Chesham, Buckinghamshire)
My modem reports:
DownStream Connection Speed  8096 kbps
UpStream Connection Speed 448 kbps
I'd really like to get this working.
Thanks!

[#2]

Apologies for replying to my own post.
Web-based speed tests are varied but coming in quite a lot lower than my modem/router reports:
download: 2500 - 6500
upload 350 - 450

[#3]

Hi Dave,
Do you notice any issues when trying to view web pages at all?
I'm just wondering if your connection itself is actually dropping, thus causing the problems you speak of.
It could also be possible that your problem is down to MTU/rWin values.  We've got a handy video showing you how to set these up here:
http://www.plus.net/support/broadband/troubleshooting/rwin_video.shtml
This may also help to ensure that you're getting optimal throughput speeds.

[#4]

I run a web dev company and i am online all day most days and have no problems with web or email (I have used PlusNet for 4+ years).  I'm no expert with networking tho!
I cannot get the tweak tester to work unfortunately.  It just says "* Downloading file of size 1024000: " and hangs.  I have followed the instructions and edited my Windows firewall (XP) by going to Advanced tab, selecting "1394 Connection" clicking "settings..." and added services on my local IP 192.168.0.2 External port 8086, internal port 8086 and same again for port 8085 (should these be both internal and external port numbers?)
I have a Netgear DG834PN router/modem running on IP 192.168.0.1 but cannot see any port settings in there

[#5]

Hi Dave,
Try downloading DR.TCP as per the video tutorial and then enter these settings:
MTU: 1430
Receive Window: 111200
Make sure that you also set the MTU as 1430 on your router and then reboot both your router and computer and see how you get on.

[#6]

I disabled my firewall temporarily but still didn't work!  have downloaded Dr TCP and set those settings. Will let you know how I get on -- thanks for help so far.

[#7]

Quote from: Jameseh

MTU: 1430 Receive Window: 111200 Make sure that you also set the MTU as 1430 on your router and then reboot both your router and computer and see how you get on.

Can I ask why 1430 is suggested as it seems rather low.
My Netgear Router (DG834GT) has always had it's MTU set to 1500.
PC MTU should be the same size.

[#8]

Hi,
I personally saw an increase in throughput of roughly 3.5Mbps when I changed my MTU to 1430.
Why did I select this amount?  Dave told me to

[#9]

is dave the guru round here?! 

[#10]

What version of messenger are you using if its the live one that could be the problem. The new one has loads of problems which send the cpu to 100% there are 369000 post if you do a google search for it.
It can happen if you have a large contact list or if windows update is running but there is no fix for the problem at the moment.
As the cpu goes to 100% everything stops

[#11]

just to let you know that changing the MTU appears to have worked (for skype at least).  Thanks for the info!