Channel 36, bandwidth auto

I have upgraded the firmware to the latest version, this had no effect on wireless speeds. By changing the channel on the 5 Ghz band I am now getting 160 mbps, however I did not have the same luck...

Model : Hardware Version : Firmware Version : ISP : Hello I am getting only 50mbs download speeds with the Archer C9, both on 2.4 and 5 ghz. Definitely the router as an RCN tech attached his router...