Hi, we’ve an annoying problem with voicemail. Any help is highly appreciated. Thanks and best regards, Fabian
PROBLEM DESCRIPTION
We’re experiencing severe audio problems with voicemail recordings on our Asterisk servers. While systems announcements (especially voicemail menus and personal announcements) are replayed cristal clear, the recorded voicemails are often choppy and miss the audio signal in a range of fractions of a second up to several seconds. The problem seems to be some how related to the overall call/system load, as it appears beyond 20 open channels and a load of approx. 1.2.
ENVIRONMENT
INTEL DUO CORE 2,6 GHz, 2GB RAM
openSuSe 10.2
Kernel 2.6.22-5-31 with HP Timer Support and Timer set to 1000hz
mysql 5.0.26
Asterisk 1.4.11 with ARA (SIP, QUEUES, VOICEMAIL) but static dialplan
TC400B trabscoder card installed and configured
Zaptel 1.4.8 with wtc4xx and ztdummy support with zttest reporting 99,99X% timing accuracy even under high system load
SIP-only environment
FURTHER DETAILS
voicemail.conf
[general]
format=wav|gsm|wav49
fromstring = XXXXXx
emailsubject = Neue Sprachnachricht von ${VM_CIDNUM}
emailbody = XXXXXXXX
attach = yes
maxmsg = 100
maxmessage = 180
minmessage = 3
maxgreet = 60
skipms = 3000
maxsilence = 10
silencethreshold = 128
maxlogins = 3
emaildateformat = %d.%m.%C um %H:%M:%S
serveremail=XXXXXX
attach=yes
skipms=3000
maxsilence=10
silencethreshold=128
maxlogins=3
odbcstorage=asteriskVM
odbcstoragewrite=asteriskVMwrite
odbctable=tblvoicemessages
emaildateformat=%A, %B %d, %Y at %r
sendvoicemail=yes
Log of voicemail recording
– Recording the message
– x=0, open writing: /var/spool/asterisk/voicemail/K0001/121/tmp/dqaSDF format: wav, 0x875db38
– x=1, open writing: /var/spool/asterisk/voicemail/K0001/121/tmp/dqaSDF format: gsm, 0x8cef3c0
– x=2, open writing: /var/spool/asterisk/voicemail/K0001/121/tmp/dqaSDF format: wav49, 0x8e7d9f8
– User hung up
== Parsing ‘/var/spool/asterisk/voicemail/K0001/121/INBOX/msg0000.txt’: Found
lsmod excerpt
wctc4xxp 54324 0
zttranscode 12168 1 wctc4xxp
firmware_class 14080 1 wctc4xxp
ztdummy 8376 0
zaptel 190084 26 zttranscode,ztdummy
dmesg excerpt
Zapata Telephony Interface Registered on major 196
Zaptel Version: 1.4.8
Zaptel Echo Canceller: MG2
ztdummy: Trying to load High Resolution Timer
ztdummy: Initialized High Resolution Timer
ztdummy: Starting High Resolution Timer
ztdummy: High Resolution Timer started, good to go
Zaptel Transcoder support loaded
ACPI: PCI Interrupt 0000:04:01.0[A] -> GSI 22 (level, low) -> IRQ 19
Registered codec translator ‘DTE Encoder’ with 92 transcoders (srcs=0000000c, ds
ts=00000101)
Registered codec translator ‘DTE Decoder’ with 92 transcoders (srcs=00000101, ds
ts=0000000c)
Zaptel DTE (G.729a / G.723.1) Transcoder support LOADED (firm ver = 6.12)
Found and successfully installed a Wildcard TC: Wildcard TC400P+TC400M
MY QUESTIONS
- Is this problem and the root cause known? I googled a lot and couldn’t find hints beyond installing the transcoder card and recompiling the kernel with high precision timer support and 1000hz timer accuracy…
- Any idea/work around to overcome this issue? Would a ramdisk for the voicemail sppol area help?
- Any further information required to investigate the problem?