We managed to resolve this by doing a few things.
A: Adjusted the sector antenna downtilt from around 5-10 degrees to only 3 degrees.
B: Changed the preambles from long to short on both the AP's and the clients (compatability to performance)
C: Replaced all Cisco equipment with other better performing, better supported, less expensive products.
We now have over 60 installation sites in a 10 mile by 20 mile valley, and they run great!
The number one problem was using Cisco prodocts for Wisp use, there are far better Wisp concerned products. Cisco is fine for normal office/enterprise use in very short ranges, but almost useless for rural long-range WISP. The other product vendors give far better, decent support at no extra charge (unlike Cisco), have better throughput, better security, better range. We are using a mix of several products (Cabletron, Microtik, 3com, Netgear, Linksys, Lanready, Airbridge (and other series), and others). They all interoperate well with each other, unlike the Cisco products. And have been far more reliable and less headache, and less expensive, and made our customers and our bottom line much happier too.
We are just trying to sell off all our Cisco equipment now, but very few seem to want it for some strange reason. I guess ebay is next.
