4690 not initing far side audio?

[m4ilm4n]

Got a weird one - we have a 4690 speakerphone in one location, and when it calls stations at another location across a WAN link, sometimes the far-side audio does not initialize (but sometimes it works). In other words, the call receiver can hear the speakerphone, but the speakerphone cannot hear the call receiver. What makes it weirder is that the second station can call the speakerphone and it'll work every time. We've tried this with two different 4690s with the same results, so I don't think it's hardware. Not sure of the firmware rev, but it's probably at least 2.6.

The call crosses two network regions, 1 and 2. I have verified that both stations are on the voice VLANS, and that the respective stations are configured correctly in the switch.

Here's a trace for a call that worked:

list trace station x471                                                Page   1

                                LIST TRACE

time            data

16:11:36     dial x540
16:11:36     ring station    x540 cid 0x2bb
16:11:36     G729A ss:off ps:20 rn:1/2 xxx.xxx.1.142:2592 xxx.xxx.2.205:2842
16:11:36     xoip: fax:Relay modem:off tty:US uid:0x936 cid:0x2bb
16:11:37     active station    x540 cid 0x2bb
16:11:37     G729A ss:off ps:20 rn:2/1 xxx.xxx.2.87:3230 xxx.xxx.1.142:2592
16:11:37     G729A ss:off ps:20 rn:1/2 xxx.xxx.1.142:2592 xxx.xxx.2.87:3230
16:14:29     idle station    x471 cid 0x2bb

I can try to get a trace of a call that doesn't work, but being sporadic it's hard to pin down. What I did notice is that cross-region calls like this use a different codec set than other calls:

Codec  Codec 1     Codec 2     Codec 3     Codec 4     Codec 5
Set

  1    G.711MU
  2    G.729       G.711A
  3    G.711MU

Should I try changing set 2? Or is there something else I need to look at?

TIA

John

 

[m4ilm4n]

Sorry - should have added that these are IP phones on a G700 running R012x.01.1.414.1.

 

[m4ilm4n]

OK - more info:

Got a single trace of a failed call, and what would normally be these:

17:01:37     G729A ss:off ps:20 rn:2/1 xxx.xxx.2.87:3230 xxx.xxx.1.142:2592
17:11:37     G729A ss:off ps:20 rn:1/2 xxx.xxx.1.142:2592 xxx.xxx.2.87:3230

only shows this:

17:01:37     G729A ss:off ps:20 rn:1/2 xxx.xxx.1.142:2592 xxx.xxx.2.87:3230

We're currently moving the speakerphone to directly wire it to the network switch (removing the house wiring from the picture).