Hi fellow n900 users. I have had a disappointing experience doing skype-to-skype calls recently with my n900. The situation was as follows:

Friend on windows - me on windows ---> very good audio quality

Friend on windows - me on n900 ---> very poor audio quality


Both my laptop and my n900 were in the same wifi network, so I discarded any 3G related issue.

Of course I couldn't find any place to configure it on the phone. Not in the skype account settings, nowhere. After lots of googling and forum searching, I couldn't either find any clue to improve sound quality. Then I thought: silly you, there must be just a /etc configuration file.

And there it was:

/etc/skyhost/skypeaudiocodecs.conf


[G729]
payload-type=18
frequency=8000
channels=1
packet-sizes=20,30,40
default-packet-size=40
min-bitrate=8000
max-bitrate=8000

[PCMA]
payload-type=8
frequency=8000
channels=1
packet-sizes=20,30,40
default-packet-size=40
min-bitrate=64000
max-bitrate=64000

[PCMU]
payload-type=0
frequency=8000
channels=1
packet-sizes=20,30,40
default-packet-size=40
min-bitrate=64000
max-bitrate=64000



First I found somewhere that the G729 codec was used for skype-to-phone calls. I don't know if I am right at that point. So since I'm not interested on that at this moment, I left it untouched.

In the other two codecs I have supposed that the channels lines refer to mono or stereo. I changed them to 2.

I have also tweaked bitrates up to 128000 and frequencies up to 32000. I have noticed some improvements, but still the quality is not as good as in a laptop-to-laptop skype call.


For the other parameters, payload-type and packet-size, I haven't changed anything because I'm not sure what's the effect.

Has anyone had any experience on this kind of tweaking? What would be the configuration that brings the best audio quality? Would anyone like to try and share what he / she finds out?

Thanks in advance and cheers to all the maemo community

Javier

I had terrible troubles with Skype over 3G - WiFi was better but still not perfect.
For me, the best method was to avoid Skype and use the googlechat instead - much better quality.

From the way my 3G data was used up, I can say that skype was using approximately twice the bandwidth that Gchat was.

I would be interested to see if Skype could be improved to the levels of Gchat.

Yeah I prefer gtalk too, but since some of my contacts are only on skype, I am using it as well. I'm over wifi so i dont care about the bandwidth now, I'm just figuring out to what extent the quality can be improved.

Few minutes ago I have tried to make a videocall thru 3G using google and quality was horrible, almost unusable. But hangup and tried again (same 3G connection) using skype (against same partner) and quality was just fine.

I have the same problem. It's barely missed first part of word. I presume it looks like the pulseaudio problem because one is eating about 40% CPU when skype is running and probably has high latency effect at begin playing.

I think I was being too optimistic. The changes I did in skypeaudiocodecs.conf don't seem to have any effect. I keep calling echo123 and finding the lady's voice darkened and very poor in high frequencies.

I own an android phone too and the same test, attached to the same WiFi network, gives me a much better sound quality. In android skype the lady sounds clear.

Repeating the same echo123 call with 3G connection in my n900 doesn't make any difference.

I also want to tell that I'm not meaning about choppiness or stutterness as I have read in other threads here.

So can anyone help? What's the matter with skype in the n900?

What is this skypeaudiocodecs.conf file for? I have read that skype uses SILK proprietary codec for skype-to-skype calls. But I can't see it in the conf file. Can I add an entry in the file with its settings and make skype use it?

Too many questions. I hope anyone can help me, I'm disappointed because I don't understand why maemo skype performs worse than on android or windows.

Thanks!!

I encourage above because I was looking for working out around Internet but useless. It's pity. Such powerful device with poor quality skype working.

Help people!

I've read the pulseaudio threads too, but why poor audio quality only happens with skype and not with other software using pulseaudio? My mp3 playback is just fine, and so it is playing any movie with mplayer. I don't understand why precisely skype has the problem.

No, I'm saying that there is lack before sounding a word. And It seems there are two problem: one before and poor quality sounding.

By the way there is no such problem on n810.