After upgrading from .243 to .278, devices that were previously at the same distance from the AP (line of sight, no blocking objects and within 20 feet) went from no latency to fluctuating signal strength and periodic latency/lag/jitter under .278. This is on an R710 with <20 clients (most being idle).
After reverting to .243 the issue disappeared.
This R710 is not the master and the client is connected via 802.11ac.
