BCM450 clicking noise on IP sets

[foneman1]

I have newly installed BCM450 R1 with 47 IP phones that having clinking noise. IT people is telling me that I do not have enough bandwidth on the phone system. RTP session telling me that I have an average bandwidth of 700Kb. Do I have control of The bandwidth on the BCM? IT people say that I do, but I do not think so. We are using Nortel 5520 switches. Thank you in advance.

 

[Dasheen]

Customer provides bandwidth. BCM codec helps determine how much u use of it. What codec? Payload? Does the customer have vlans setup? Is your system full patched?

 

[foneman1]

They are using G711. Not sure about the payload, they do have Vlans setup. The system is fully patched except of the latest SU patch (I tried to install it and it told me this patch is obsolete. I am sure you know about this issue). What the payload and Vlan should be set for?. Thank you so much.

 

[IPOfficeIreland]

47 IP phones on VLan shouldn't have clicking, check these reference sites for payload and bandwidth allowances:

http://www.cisco.com/en/US/tech/tk652/tk698/technologies_tech_note09186a0080094ae2.shtml

http://www.newport-networks.com/cust-docs/52-VoIP-Bandwidth.pdf

I would check your PRI/Pri Card for clicking, might be a clocking issue. Can you connect 1 IP phone directly and test it?

 

[foneman1]

Thanks for the links. I have this problem when people talking internally also. Thanks.

 

[IPOfficeIreland]

I still wouldn't rule out hardware. Does it happen on all phones and/or on all calls?

The voice compression card on the BCM, newtwork switch, BCM itself all need to be considered here.

 

[telcodog]

When it comes to IP phones (or anything related to voip) on their networks, IT people always blame the phone system. It's never their fault until we prove it, and even then, some of them stay in denial.

In this case, I would bring in my own data switch, disconnect their network and connect it, then connect a few of the ip sets to it and make some test calls. My bet is that it's one of their data switches causing the problem.

Good luck and let us know how you make out.

 

[foneman1]

The Customer replaced the 5520 switch this morning, and so far we had no complaints. Thank you all.