[asterisk-users] Remote hold on PRI

[Gaëtan Minet]

Hi everybody

We have a strange problem with several asterisk servers (Version  
1.4.11) using PRI cards (tied to telco here in Belgium).

Indeed we noticed that whenever a local user places an outgoing call  
through the PRI (and telco) to another IPBX (tied to telco using BRI  
or PRI), if the remote party places the call on hold, the caller hears  
the _local_ music on hold instead of the remote one.  In fact we can  
briefly hear the remote music on hold start, then it is replaced by  
the local one.

More precisely:

Company 1 uses an asterisk server with a PRI card tied to the telco.
Company 2 uses any PBX that ca place calls on hold and is tied to the  
telco using a digital interface (tested with BRIs and PRIs)

A (company 1) calls B (company 2)
B answers and park or places the call on hold
A hears the MOH of company 1.

The same happens when calling a mobile: when the mobile user puts the  
call on hold, instead of hearing the mobile operator's own moh, the  
calling user hears the moh of his own company asterisk.

I think this has something to do with REMOTE_HOLD notifications on PRI  
lines that gets reported back to the calling asterisk server, which in  
turn somehow puts the bridged (SIP) channel on hold, but I can't find  
much more information about this.
Is this the expected behavior ? A feature or a bug ? Do you know if  
this can be tuned/tweaked/disabled (i.e. filter or ignore this  
signaling on the zap channel(s) ?)

Kind regards
Thanks

NB: Oddly enough, when the local user hears the music on hold, his own  
channel (a local SIP phone in this case) isn't reported as "On Hold"  
when issuing "sip show channels" in cli,  and no AMI Hold/Unhold  
events are generated. I double checked, the MOH that gets played is  
the one specified in sip.conf, NOT zapata.conf.