We are getting very high retry counts on various Access Points - some reaching as much as 80% - on the 2.4GHz channel. I've changed channels from 1, to 6 and 11 and still these high utilisation levels are there. How can I investigate and cure?
Check the AP Neighbour count. If it is high (more than ~10-15) then you may have AP's too close together and/or have the EIRP (transmit power too high)