Voicemail stops when PSTN lines in use - any pointers?

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Feb 1st, 2010
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I'm trying to debug some issues with my first SPA9000+SPA400+SPA932 installation.

All firmware updated. System initially configured with the wizard, then manually.

There are 6 SPA932 handsets.

Voicemail is configured for each user and we're using 2 PSTN lines through the SPA400.

The SPA400 is connected to Line 2 on the SPA9000.

No SIP trunks at this stage.

The voicemail & PABX functions of the system seem fine for internal calls.

The voicemail stops working when both PSTN lines are in use.

The voicemail functions recover once the PSTN calls are finished.

I've read somewhere that more than an extra SPA400 is required if you have more than 2 PSTN lines and want voicemail, but I thought the configuration in question should have been OK.

Calls made through the PSTN lines have almost continual short duration breaks for the person listening on the outside.

Listeners inside the netork do not experience any breaks.

I would be grateful for any pointers to help me debug these issues.

Thank you, Nigel

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David Hornstein Mon, 02/01/2010 - 22:58
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Hi Nigel,

Sound like you are doing nothing wrong, it is highly recommended that if you are using the VM module within the SPA400 that you also limit the number of active FX0 ports to a maximum of two.  Which you have done.

Ok Maybe the VM prompts running in a default highly compressed CODEC is slowing down the operation of the SPA400.

Might I  humbly suggest you try to use a uncompressed VM prompts on the USB drive rather than the default compressed prompts.  Uncompressed prompts will mean the SPA400 CPU does less work whilst call are coming in.  Hence better opportunity for clear VM.

Try the wonderful procedure as documented by Pat Born at the following link;


regards Dave


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