IP 8821 phone "network busy"

[rob.drye]

New IP 8821 phones frequently come up with failed calls due to "network busy", though sometimes calls work fine.  7925 phones operate all of the time.  The wireless config is unchanged in several years - MAC authentication, Platinum QOS, no CAC, WMM allowed but not required.  Anyone else seeing this behavior? I'm going to cross-post on Wireless Voice and Video.

Phone load is sip8821.11-0-3-6  CM 10.5.2.12901-1 WLCs are 8.0.133.0

[Brandon Buffin]

Take a look at this related bug - https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvc52145

Brandon

[rob.drye]

Unfortunately, the workaround in the bug "Disable ACM for voice & video" isn't going to help since ACM is already disabled...

[rob.drye]

11-0-3SR1-1 appears to fix the problem.

[william666666]

We found a setting to toggle that seems to have helped. 

In Cisco WLC 9800-40 go to Configuration -->  media parameters --> Call Admission Control -->  clear the Admission Control (ACM) checkbox. 

Not sure if toggling that setting off solved the problem entirely, but so far no new problems reported.

[tyoung008]

This worked for me.  Thank you @william666666 !!!!

[nitish107sinha]

Have ordered about 10,  8821 cisco wireless phones. Unable to figure out why incoming calls and outgoing calls from the wireless devices shows as "Network Busy" message on the phone?

Any help will be highly appreciated.Thank you! 

[Aeby Vinod]

What firmware version are the 8821's running on?