Which wireless feature must be disabled to maintain voice call quality over a WLAN?

Aggressive load balancing can negatively impact voice call quality by forcing a client to disassociate from an access point (AP) and reassociate with another, even if the current connection is stable. This reassociation process introduces delays and potential packet loss, which are detrimental to real-time voice traffic. Priority queuing, when properly configured, actually helps maintain voice quality by prioritizing voice packets over other traffic. Dynamic transmit power control helps optimize coverage and minimize interference, which can improve voice quality. Fastlane is a Cisco feature designed to improve quality of service (QoS) for Apple devices, including voice applications, so disabling it would be counterproductive.