Based on my understanding from your dialplan and sipp options, I assume that you are testing 2-way audio?
Need to know more as to what you meant by “some call fall down”, probably by posting the sipp result.
I had made changes to my dialplan, which was used to record inbound voice generated by the sipp command to Asterisk voicemail -
./sipp -sf uac_pcap_tt-monkeys_ilbc.xml -nr -l 40 -s vm -r 2 -i 192.168.80.140 -p 5078 -m 40 -mp 8888 -mi 192.168.80.140 192.168.80.140 -trace_err
As you would have noticed, the options were much less stringent than yours, but it attained positive outcome for my case -
------------------------------ Scenario Screen -------- [1-4]: Change Screen –
Call-rate(length) Port Total-time Total-calls Remote-host
2.0(0 ms)/1.000s 5078 39.29 s 40 192.168.80.140:5060(UDP)
Call limit reached (-m 40), 0.959 s period 18 ms scheduler resolution
0 concurrent calls (limit 40) Peak was 39 calls, after 19 s
0 out-of-call msg (discarded)
1 open sockets
21982 Total RTP pckts 0.064 last period RTP rate (kB/s)
Messages Retrans Timeout Unexpected-Msg
INVITE ----------> 40 0 0
100 <---------- 40 0 0
180 <---------- 0 0 0
200 <---------- E-RTD 40 0 0
ACK ----------> 40 0
Pause [ 1000ms] 40 0
[ NOP ]
Pause [ 17000ms] 40 0
[ NOP ]
Pause [ 1000ms] 40 0
BYE ----------> 40 0 0
200 <---------- 40 0 0
------------------------------ Test Terminated --------------------------------
----------------------------- Statistics Screen ------- [1-4]: Change Screen –
Start Time | 2006-04-05 01:06:12
Last Reset Time | 2006-04-05 01:06:51
Current Time | 2006-04-05 01:06:52
-------------------------±--------------------------±-------------------------
Counter Name | Periodic value | Cumulative value
-------------------------±--------------------------±-------------------------
Elapsed Time | 00:00:00:963 | 00:00:39:319
Call Rate | 0.000 cps | 1.017 cps
-------------------------±--------------------------±-------------------------
Incoming call created | 0 | 0
OutGoing call created | 0 | 40
Total Call created | | 40
Current Call | 0 |
-------------------------±--------------------------±-------------------------
Successful call | 3 | 40
Failed call | 0 | 0
-------------------------±--------------------------±-------------------------
Response Time | 00:00:00:000 | 00:00:00:028
Call Length | 00:00:19:346 | 00:00:19:262
------------------------------ Test Terminated --------------------------------
The “uac_pcap_tt-monkeys_ilbc.xml” file was modified from the original uac_pcap.xml, using a pre-recorded stream playing the Asterisk tt-monkeys.gsm audio coded with ilbc, at a rate of 2 calls/sec up to a max of 40 concurrent calls at any time. I played the recorded voicemails with Wavepad and the quality differences in comparison with tt-monkeys.gsm was acceptable.
Need more info on how you try capturing with Ethereal to help further. I had recorded 3 pcap streams, will email if needed.