I'd recommend checking the Wireless>SSID>Edit Settings 'Wireless Options' section of your SSID. Also check Wireless>Radio Settings.
Here are my settings but some adjustments to either of the two above sections may help with your issue. Also worth considering if it is a device issue or is this occurring on multiple HRT-500's?
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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