As a quick test, can you check if using minstrel makes a difference ? Just disable the CONFIG_ATH9K_RATE_CONTROL option in the kernel config and syslog would show:
ieee80211 phy28: Selected rate control algorithm 'minstrel_ht'
The switch has been made recently: http://marc.info/?l=linux-wireless&m=137048839031184&w=2
As a quick test, can you check if using minstrel makes a difference ? Just disable the CONFIG_ ATH9K_RATE_ CONTROL option in the kernel config and syslog would show:
ieee80211 phy28: Selected rate control algorithm 'minstrel_ht'
The switch has been made recently: marc.info/ ?l=linux- wireless& m=1370488390311 84&w=2
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