Increasing SIP volume in freepbx/asterisk/elastix/trixbox

Changing the volume of SIP/IAX calls in asterisk (freepbx/asterisk/elastix/trixbox distros etc.)

To change the SIP volume in FreePBX you need to edit extensions.conf and admin/modules/core/ (from which extensions_additional.conf is generated)

To set the incoming (and internal) volume search for macro-dial in extensions.conf

It should look like

exten => s,1,GotoIf("${MOHCLASS}" = ""?dial)
exten => s,n,SetMusicOnHold(${MOHCLASS})

You need to edit it to look like this, the volume (TX) and (RX) are the transmit and receive levels, they can be any integer between 0 and 10 although you're unlikely to use more than 4.

exten => s,1,Set(VOLUME(TX)=4)
exten => s,n,Set(VOLUME(RX)=4)
exten => s,n,GotoIf("${MOHCLASS}" = ""?dial)
exten => s,n,SetMusicOnHold(${MOHCLASS})

To set outgoing volume search for macro-dialout-trunk in /var/www/html/admin/modules/core/ (or where ever your FreePBX install is located)

It should look like

$context = 'macro-dialout-trunk';
$exten = 's';
$ext->add($context, $exten, '', new ext_set('DIAL_TRUNK', '${ARG1}'));

You need edit it to look like this, again setting the volume levels

$context = 'macro-dialout-trunk';
$exten = 's';
$ext->add($context, $exten, '', new ext_set('VOLUME(TX)', '4'));
$ext->add($context, $exten, '', new ext_set('VOLUME(RX)', '4'));       
$ext->add($context, $exten, '', new ext_set('DIAL_TRUNK', '${ARG1}'));

Reload FreePBX and you should notice your calls are now much louder!

NOTE: This will only work out of the box with an asterisk 1.6+ system (the volume function doesn't exist before version 1.6) if you are running an older version it is possible to backport the volume function - contact us if you need this doing.

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