you're welcome.
your MIR Bandwidth Settings are OK already.
try to enable Hi Priority Channel.
also, go to AP Evaluation and look for the Color Code which has the lowest Jitter, highest RSSI and lowest Power, and upon meeting those and if possible, get the color code which a fewer UserSectorCount.
in the Configuration page, put your your desired color code. click save and initiate reboot (canopy not your pc).
do not touch anything else.
hope that helps.
kindly post your speed score after.