Don't you want them to switch to the AP closest to them for best signal? You may also want to look at Wireless>Radio Settings and decide if you want 'Client balancing' turned on or off. But I'd assume that would cause the opposite issue where you may stay connected to an AP that is not optimal based on the load of clients on that AP.
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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