[QoS ISSUE] on Kernel 2.6 ztdummy makes no improvement

Asterisk Asterisk Support
1

[PROBLEM:]

I installed Asterisk 1.0.9 on Kernel 2.4 and the voice stream sounded like c…r…ap…

After reading comments that this poor voice quality is because of the timing source issue, I upgraded kernel to 2.6.13.2 and loaded ztdummy as module, along with the zaptel. They both show listed on lsmod.

But the voice quality hasnt improved at all. Still vve…rry… c…r…ap…ppppy…

System info: XP2400, 1GB RAM system running RH9, with 4Mbps connection. (It can’t be hardware or bandwidth issue.)

ZTDUMMY shows here, thus I assume it is loaded:

new*CLI> zap show status Description Alarms IRQ bpviol CRC4 ZTDUMMY/1 1 UNCONFIGUR 0 0 0

[QUESTION:]

[size=150]Is there anyway to check if ztdummy is doing its job to improve the timing source situation?[/size]

2

Sorry, I do not have an answer. But I encounter the same problem on Fedora Core 4.
Regards Jan.

3

If you are running an X Server on the machine, you should not, as it will compete for system resources with Asterisk. Any Asterisk server should be ‘headless’.

4

You say the sound quality’s crap - but that doesn’t mean anything at all! What sound quality? How are you using Asterisk?

What phone(s) are you using?

5

Hi,
I am using Asterisk in a very simple setup, to expand it later.
I can use softphones, but the problem can also be demonstrated without them. To demonstrate the problem I can use my AVM-B1 active ISDN card. I configured extensions.conf to only playback a message when dialed in over capi-chan. When I dial in either with an normal phone or a mobile without ztdummy loaded I can hear the message clearly. When I modprobe ztdummy whithout any visible error messages and dial in again I hear the message very garbled.
Regards Jan.

6

Hi,
If you want to know how garbled, dial +31299414650
Regards Jan

7

Hi,
The same result with SJPhone, even without XServer running.
Regards Jan.

8

oh! This problem with ztdummy has been fixed! They gave the patch but when i applied on it they are even worst than before i applied the patch when i run zttest. Anyone got improvements? Issit the kernel needs to be upgraded?

9

Hi,
I switched to asterisk-1.2.0-beta2 and checked out chan_capi from cvs.sourceforge.net/chan-capi. The ztdummy included is an improvement. Messages are heard clear again when dialing in over the phone. Only some more testing on conferences needs to be done.
Regards Jan.