> I’d suggest try recording in ulaw first and then convert all to wav after.
> It may have something to do with timing since you’re using iax, what are you using as a timing source? Hardware or software?
Sent from my iPhone
I believe I am using software, since I don’t have any special hardware
installed. I do have a Digium card somewhere in a box. I can try
recording in ULAW, but I’m unsure how to convert it to WAV. I think
Asterisk can do it, so I’ll give it a try and look it up.
If I can get this sorted out, I think it’ll be a great podcast solution.
On Mon, Mar 21, 2011 at 8:33 PM, Neeraj Chand
I tried recording a podcast a couple days ago. I recorded in ulaw format,
and converted to wav afterwards, as you said. Our session ran over double
the length they usually do, over 3 hours. The sync is much better than my
first tests, and that is with the jitter buffer enabled – or at least, I
believe it is – I saw this output:
*CLI> iax2 show channels
Channel Peer Username ID (Lo/Rem) Seq (Tx/Rx)
Lag Jitter JitBuf Format FirstMsg LastMsg
IAX2/tayler-129 70.xx.xx.169 tayler 00129/25402 00048/00048
00075ms 0065ms 0119ms ulaw Rx:NEW Rx:ACK
IAX2/josh-346 216.xx.xx.2 josh 00346/21060 00138/00175
00088ms 0069ms 0114ms ulaw Rx:NEW Tx:ACK
IAX2/dana-1985 66.xx.xx.7 dana 01985/21748 00013/00043
00082ms 0005ms 0079ms ulaw Rx:NEW Tx:ACK
3 active IAX channels
*CLI> Resyncing the jb. last_delay 67, this delay 2079, threshold 1126, new
Resyncing the jb. last_delay -189, this delay 1097, threshold 1136, new
However, the sync goes out of sync slowly. I recorded both in and out
channels for all three participants, and even the pairs don’t match up
properly. System load was around 0-0.01 the whole time, according to top.
Now, for the first hour or so, the sync was fairly OK (only minor adjustment
needed), but it drifts after that and I need to adjust more frequently in
I am not sure which timing modules I am using. I tried to find the one you
$ sudo find / | grep -i dahdi_dummy | wc -l
I figure this is because I compiled Asterisk from source (because I had
originally planned to use wideband codec but couldn’t find any
cross-platform IAX client with wideband support). Is there a way to tell
which timer module is in use, or which I compiled in? If I specify in
modules.conf which to noload and which to load, would that do the trick (and
does that even work when compiled from scratch?). I can always recompile,
and I still have my source tree. I also found my old Digium card (it’s
around 6 years old).
Thanks for your help.