Irvan,
If you only wish to use channel 1, 6, and 11 in 2.4GHz, you should be using Background Scanning
under Configure/Services/Self Healing. If you have selected Channelfly, you need to permit all the
2.4GHz channels 1-11 that its designed for. Most modern clients can use all 11 2.4GHz channels.
How many APs do you have and how close together, enough that clients can roam if they need to?
Are you on the latest ZD firmware, to help rule out any bugs with ZD/APs? Have you reviewed your
debug logs, maybe focused on a client MAC who says he/she has problems, and capture the AP
support info when they say so?
First paragraph is config, second is troubleshooting. Let us know.