After having worked on countless Cisco WLAN VoIP deployments a general rule of thumb from Cisco TAC is to disable TKIP countermeasure on ALL voice WLANs and lessen the timer for DATA WLANs. Again this is all subject to your comfort level and performance requirements. Personally, I can't say I have ever seen this to be an issue or had an issue that was directly related to the countermeasure. But something to chew on!

TKIP countermeasure mode can occur if the Access Point receives 2 message integrity check (MIC) errors within a 60 second period. When this occurs, the Access Point will de-authenticate ALL TKIP clients associated to that 802.11 radio and holdoff any clients for the countermeasure holdoff time (default = 60 seconds).

(Cisco Controller)config wlan security <tkip> hold-down <seconds> <wlan id>

Note:  Configures TKIP MIC countermeasures hold-down timer (0-60 seconds)

The following command disables TKIP countermeasure on WLAN 1 

(Cisco Controller) >config wlan security tkip hold-down 0 1