Wireless IP Phones getting 1 second latency

[rlortiz]

I have a remote site customer with a Cisco WLC 4404 and 1130 Access Points. They are using SpectraLink wireless phones with no probem for about 6 months. Recently, there is about a 1 second latency when using the IP Phones. NetStumbler is seeing various signaling to go low as it roams from 1 AP to another. The distance between the 3 APs is 85 feet. What is the best way to troubleshoot this problem? Can we do anything with the AP to enhance the signaling during the roaming process?

The initial firmware was 4.0.155.5 and has been upgrade to 5.0.148 to see if it helped. It didn't.

Any help would be appreciated.

[dennischolmes]

Check the number of clients on the APs when roaming occurs. Make sure that aggressive load balancing is disabled on the controller and that client usage does not exceed 12 total users per AP and no more than 5 calls per AP at a time. I know Cisco has some other numbers out there but these seem to work best. Make sure you are having no authentication issues either. Finally, if all else fails, do all the debugs on the controller and do some packet captures using Wire Shark or a comparable product.