By default enabled. With WMM enabled, the EAP devices have the QoS function
to guarantee the high priority of the transmission of audio and video packets.
If 802.11n only mode is selected in 2.4GHz (or 802.11n only, 802.11ac only, or
802.11 n/ac mixed mode in 5GHz), the WMM should be enabled. If WMM is
disabled, the 802.11n only mode cannot be selected in 2.4GHz (or 802.11n only,
802.11ac only, or 802.11 n/ac mixed mode in 5GHz).