Notices

Guys,

I have been in touch with Olivier Crete (from Collabora) regarding this bug via irc. He looks after the voice quality issues in N900. I setup a freeswitch server against which Olivier did some siptraces.

He believes that there is a bug in gstreamer rtp jitter buffer (gstrtpjitterbuffer) library in N900. That bit of the code is very touchy. He is the person responsible to fix the code in N900 but presently he has no free time. I did ask him when he could fix this bug but he did not give any time-frame.

I did carry out tests using empathy (on PC) which also uses the gstreamer and telepathy-sofiasip library (same as N900) but the voice was very clear. It would seem that the implementation on N900 has issues. Apparently, the same upstream code will be used in meego as well, so nothing exciting on that front.

I also asked Nokia Wifi developer for recommendations on any good router (with sip calls) which support Power Saving Mode (PSM) but the response wasnt very useful
Hopefully, Olivier will be able to fix this bug some time in the future. If anybody understands gstreamer please have a look at gstrtpjitterbuffer.

g729 is VERY cpu-intensive.

Hello all,

Where do I change the codec on my phone?

Does it need changed on the server (asterisk) side?

-Eric

Best is to change it on the server side. E.g. for using ilbc add the following to your asterisk settings:

I the meantime I found a solution that works for me. I use the ilbc codec for a few weeks now without choppy audio.
To archive this I made the following two changes to my n900:
1.) Install the new pulseaudio package provided by the user MohammadAG as discussed here
2.) Set the processor speed to 600MHz (fix) during sip calls (I think the stock kernel does this, however it seems not to work with the power Kernel).
To set the processor speed to 600MHz during a sip call I use a dbus script. I added the following config file to the /etc/dbus-scripts.d/ directory with the following content:
And created the two files in /usr/sbin/.
speedadaptfix
speedadaptnormal
As said before this works perfect for me. No choppy audio anymore!

Ok guys I have a disappointing news from Collabora dev. This bug is not fixed yet and so will miss the 1.3 firmware release!

I just installed the libpulse package provided by brad112358 in the thread alex25 linked. No other changes, stock kernel.
And for the first time since I owned the N900, I can actually use it with Skype!
Only tested Skype-to-Skype over WLAN, but it worked for the ten minutes I tested.
Thanks for the link, alex25!

I also installed brad112358's libpulse0 package (linked at http://talk.maemo.org/showpost.php?p...&postcount=113) that was referenced on the 12th page of the thread that alex25 referred to. Stuttering is as bad as ever.

The only difference I can see is that I'm running the power kernel (for kismet). (Well, and that despite many hours troubleshooting this problem, it's still unusable it with Skype/VoIP)

I also tried MohammadAG's multipackage approach that is the topic of the thread that alex25 directs to. Stuttering did not improve, and I ran into the other expected problems (ringtones, etc.)

Can anyone here comment on whether using a different program would bypass gstrtpjitterbuffer? I noticed that SFLPhone has a mispackaged, non-version-matching n900 port, but it may be more fruitful to try to straighten that out than applying ineffective patch after patch.

Did you set the CPU clock rate to a fix value during the SIP call?
(execute this command during an active call: kernel-config limits 600 600)

It works perfect without choppy audio on my setup.

it works fine over 3g , using wireless the audio is really choppy