Summary:ASTERISK-01995: VM recorded from pstn-TDM-Zap is ~-10db (low volume)
Reporter:radamson (radamson)Labels:
Date Opened:2004-07-12 09:40:27Date Closed:2004-09-25 02:09:41
Versions:Frequency of
Description:Call from pstn goes to VM via TDM FXO. Retreival of VM has very low volume. Measured with 3M 965DSP transmission test set ($3.5k) at -34db (including Plant). Repeated test several times, same results. Reboot system, same results.


Test set on pstn line to CO (-5.6db), through CO, pstn line to * (-5.6db) to VM. 1004hz tone sent at 0db. (Total cable plant loss is 11.2db, test set to *) Retreive VM call from same path results in 1004hz tone at -34db. Retreival of same VM call from ata186 (on same wire as *) indicates tone is at -22db (ata186 has -1db loss setting). Subtracting the 11.2db initial plant loss for recording the tone and -1db for ata186 indicates * is recording/playing VM at approx -9.8 db of loss. * system was rebooted, no other calls in system, no other apps running on * system, exact same results. Cable loss verified by calling CO Milliwatt (-5.6db) which is consistent with distance to that CO. Ata186 loss verified by calling * milliwatt and measuring -2.0 db. TDM-FXO loss verified by calling pstn->* Milliwatt. 3M 965DSP is new and factory calibrated. Pstn interface to * is via TDM04b FXO with rxgain=0 and txgain=0, echotraining=800. (I'm a non-programmer with 20+ years of telephone transimission engineering experience.) RichA on IRC.
Comments:By: twisted (twisted) 2004-07-13 11:59:24

Rich, there is no need to post duplicate bugs.  I'm closing this one since you filed 2023 with basically the same info.

By: radamson (radamson) 2004-07-14 14:38:12

Reminder sent to radamson9, twisted

Are you sure we should close 2022? I think its a bug with the existing app (-10 db level) to all "existing" channels, while bug 2023 is a feature request asking for a gain control specifically for pstn interface channels. If 2023 is implemented, then presumably 2022 is still around as low volume. If 2022 is fixed, that doesn't necessarily address the issues with pstn calls. Thoughts?

By: radamson (radamson) 2004-08-08 16:01:43

This is not a duplicate of 2023. Others are having this same problem and are adding their comments to 2023. This one is a bug (from my perspective) as the VM levels when using Digium cards (TDM or X100P for pstn) are -10db low in volume compared to any other pstn access. Checking VM msgs from a cell phone (as an example) is _not_ usable as the audio is so low it can't be understood.
Bug 2023 is still an outstanding 'feature request' that would stand even if this bug (2022) were fixed. Again, this bug addresses VM recording from the pstn via TDM or X100P cards "only" at -10db (excluding additional pstn losses).

By: mochouinard (mochouinard) 2004-08-08 22:32:00

TDM400 FXO module have the problem of being most of the time too low. I heard of other people saying the same thing.

By: bfranks (bfranks) 2004-08-10 21:35:26

Same problem here w/ T100P --> Adtran TA 750.

Volume is very low when Sip Phones call to hear there messages.

Volume us EXTREMELY low when they dial in from home to check there messages, can not hear messages at all unless you ae in a completely silent room listening very hard to what the message is.

By: Mark Spencer (markster) 2004-08-11 01:36:16

If you can get this duplicated over at Digium we can try to do it.  Perhaps you can talk to support (specifically James) and get him to lab it up and duplicate the problem.

What about using the record/play and also what about changing the format that you're storing it in (e.g. gsm vs. WAV)

By: twisted (twisted) 2004-08-24 13:36:37

Status request - outcome of testing?  /* Housekeeping */

By: radamson (radamson) 2004-08-27 13:08:45

Contacted James at support on 8-27-04. I will send him a step by step method to recreate the problem in the lab.

By: Mark Spencer (markster) 2004-08-28 13:45:05

Going by the comments in 2023 I think it's best to close this and link to 2023.