one phone having one way audio 1

[Jouik]

Hi
I'm facing a strange issues here.
First the story:
Our customer bought two brand new IP phones Model 1616D02A-003. I have installed those phones to customer's premises.
Both with the same static IP parameters (except for the phone's IP of course). Both phones have the same firmware loaded (ha1616ua1_350B.bin)Both phones STATION settings are identical.

Now the problem:
The first phone (lets call it number one) works just fine.
The second phone (number two from now onwards) does have a one way audio issue = nothing can be heard either through the handset nor through the loudspeaker.

Now the troubleshooting done so far and my assumptions:
1. The phone number 2 does not work (still the same issues=no audio in handset/loudspeaker) at phone number 1 cable connection either = its not a LAN cable issue.
2. Another phones, no matter if different, or of the same type and firmware works just fine on the phone 2 position (connected to the same set of LAN cables).
3. The STATION settings are identical for both the phone#1 and phone#2. Customer use CM version R015x.02.1.016.4
4. Both the phones have static IP's. The state is the same when I switch the phone IP's between themselves (e.g. phone 1 IP is given to phone 2 and vice versa)
5. Now the best thing, when I bring this phone#2 to my test LAB and register it to my LAB IPO500 server edition, the phone works OK. With the same firmware. It works OK even when I let it upgrade to the latest 390A.bin file.
6. When I bring it back to customer premises, it downgrades back to 350B.bin and the issues are the same when it boots up.

The customer used older 4610 IP Phone at the Phone2 place, but it got broken so they bought new set of phones 1616. If I connect other 4610 and register it as Phone2 it works just fine.
If I take another (older/used 1616) phone and register it as Phone2, it works just fine.
If I take the Phone1 (1616) and register it as Phone2, it works.


IP Parameters:
Phone: 10.0.0.93(Phone1) 10.0.0.61(Phone2)
Call Server: 10.0.0.50
Router: 10.0.0.1
Mask: 255.255.255.0
File Server: 10.0.0.55
802.1Q: Auto
VLAN ID: 0
VLAN Test: 60


Phone: 1616
Model: 1616D02A
PhoneSN: 17WZ19200CJ2
PWB SN: 17WZ1850CRL2
PWB Comcode: 55.62J01.061G
MAC: A4:78:86:B7:32:BE
Group: 0
Protocol: H323
App. File: ha1616ua1_350B.bin
Boot File: hb1616ua1_350B.bin
Proxy server: none
802.1X: 0

Can you please advise what am I missing? Where to look for differencies or changes? How to troubleshoot further?
change station screens of both phones

Thanks a lot.







regards
Jou

 

[joe2938]

have you tried a list trace station and compare it from phone 1 location to phone 2 location, see any differences?

 

[Jouik]

joe2938 - not yet. This is on my list together with wireshark trace.Once I get it, I can post it here.
But I'm wondering why only this one phone does it and does it only at the customer premises, not in my lab. It needs to be some settings that I'm missing

regards
Jou

 

[joe2938]

Hopefully that is why I want you to do the trace and yes very weird issue

 

[DAVIDPAYNE]

Jouik, Are there other phone that are working correctly at that Customer site?
If yes, are they on the same network segment, VLAN, etc. as the none working phone?
Does it get the same IP address range as the working phone, and it is assigned to the correct network region?

 

[Jouik]

Hi DAVIDPAYNE
- yes there are other phones working OK
- Yes they are on the same network 10.0.0.x /24 (the IPs are assigned manually)
- Yes they are on the same VLAN (at least the phones are configured for the same)
- I have even tried to assign the working phone's IP to the non working phone. Still no joy



regards
Jou

 

[DAVIDPAYNE]

Stupid question, have you tried that phone in a network port of a working phone at that site?
And have you tried a working phone in the port of the phone that does not work?
If you have, etc. then do a trace of the station, and see what that tells you. After that it wireshark.

 

[Jouik]

Yes DAVIDPAYNE i tried that too. I hope I'll be able to get to the customer's site next week to capture the traces which will hopefully tell us more.

regards
Jou

 

[dialtonebone]

Is the CM's network configuration okay? Can it talk to the media gateways and medpros? Are those configured with the right subnet masks?

 

[Jouik]

Hi all

Workaround found
For some reason, the G450 Media gateway is not updating its ARP cache, when we swap the IP Phones. Thus the UDP/RTP packets are being lost / not coming to the right phone.
Once we set up the cache to be flushed every X seconds, then we can swap the working phone for the "non-working" one and once the arp cache for that IP address is cleared on the G450 after those X seconds, we can have the audio back on the "non working phone" ! Hurray !

regards
Jou

 

[kyle555]

That's right! That's made my life difficult too!

Every once in a while i have a LSP where I can ping cdom but not dom0 or CM but not cdom on the same 8300 card and flushing the arp cache is the only way around it. I think they may have addressed it in current firmware, but I know as of 6.3 CM that problem was still present and happens once in a blue moon.

 

[Jouik]

kyle555 We are now on 7.1 and this is still happening.
Sure thing, I didn't mean to argue with you. Just mentioning its still there
regards
Jou

 

[kyle555]

I didn't say they did address it. just that they acknowledged it!