I am using Asterisk ver 1.4.23 and dahdi drivers for tdm400p card. I can use the trunk line and voice is good when calling some sip user . But when i use meetme app, instead of regular audio i hear garbled audio.
Before joining the conference , asterisk prompts me for username etc. I can hear these voice prompts without any problem but after it connects the trunk line to the conference , even the music on hold sounds garbled. Though it sounds fine if I join the conference from a SIP client. I am using gsm codecs. I would be glad if someone can give some pointers.
Which OS are you using?
I’m not sure, but could you try to load ztdummy module 
I am using kamikaze 8.09 distribution for a IXP425 based target. The kernel version is 2.6.26.6. The dahdi_dummy module is already loaded i checked.
ahh… should have tried earlier. Unloading the dahdi_dummy module made it work 
thanks for replying !!