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Hey guys,
I was wondering if you guys notice that Skype (voice) is better on 2G than 3G. I was speaking to a friend in Korea using T-Mobile 2G and it was clearer than speaking to a friend in Pennsylvania using 3G. Both friends have broadband in their respective locations. I also tried to 3G Skype call a friend in South Africa and it was pretty bad. I've done regular Skype from my laptop to all 3 of these before and its never an issue. I tether from my laptop so its the same connection.

Anyone else having 3G Skype calls that have more lag than when using 2G?

i dont think you are supposed to talk on skype with 2G network. it's not fast enough. i think by saying 2G you meant WIFI? otherwise it just beats me. if that's the case, normally wifi would bt better than 3G networks cuz the bandwidth's bigger

isnt latency the important issue here? and not necessairly bandwidth?

i think the limited bandwidth is the reason that caused the latency.

No, that's precisely my point I have a more consistent experience using 2G. I have no wifi network at home. 3G should be better but it is not. Strange...

according to speedtest.net:

3G: 136ms latency, 4.94 down / 1.18 up
2G: 342ms ping 0.19 down / 0.12 up

Skype calls on 3G should be fine but its not for some reason. Using Tunewiki I can only stream music on 3G which makes sense. What's up with Skype?

Only thing that springs to mind is that maybe your operator is somehow limiting Skype-specific traffic. Don't know why the experience would be better with 2G connection though, maybe they're limiting it only on 3G connections(?)

T-Mobile doesn't seem to care. Plus I tether from my laptop and it works fine there so I don't think they're limiting it at all.

Wild guess: on 3G, you have more bandwidth available, so skype chooses a higher bitrate, and you use more CPU on the transmission/reception side -- system becomes CPU-bound and laggy.

On 2G, it scales back to a lower bitrate, which takes less CPU cycles to send, and it becomes I/O bound and behaves "properly".

With Skype on the laptop (and thus no codec processing on N900), the N900 is I/O bound for both cases, and of course the laptop always is, so "proper" behavior throughout.

Ways to test this hypothesis: use top or similar to monitor CPU load in both cases, with the aid of echo123. Or just overclock and see if it improves 3G but not 2G; if so, you might then consider overclocking on a regular basis, at least when using Skype. (Overclock at your own risk of accelerated hardware aging and death, naturally...)

I think Benson is correct

skype is choosing a higher bandwidth codec on 3g that is causing problems(bandwidth isnt really high enough or cpu isn't up to it)